The lower limit to silver's usefulness in coinage

A detectorist in Suffolk, England recently found a beautiful halfpenny minted some time between 1625-1649, during the reign of King Charles I. This coin, captured in the video below, illustrates an important feature of coinage: the lower limit to silver's usefulness as a monetary metal.

As you can see, the halfpenny is tiny compared to the fingers holding it, which would have made it difficult to count, handle, and transfer. Storing it away in a pocket or purse would have been a nuissance, since it might have gotten lost in the folds.

Just chilling this afternoon and pottering about.
So here's a lovely little Charles I halfpenny, simple yet elegent ☺️

Found 2020https://t.co/PiKJjooe7D pic.twitter.com/87BRG2s69u

— Suffolk Detectorist (@SDetectorist) June 11, 2023

The root of the problem is that silver has always had a relatively high value-to-weight ratio, (i.e. it is good at "condensing value," as I once described here) and so attempts to embody lower denomination coins with silver don't function very well, since what is required for low denominations is a material that dissipates rather than condenses. Silver change is just too damn small.

According to the Portable Antiquities Scheme, this particular halfpenny – which is in great shape – weighs 0.27 grams and has a diameter of 10 mm. Compare that to a U.S. dime, already annoyingly small, which weighs 2.3 grams and has a diameter of 18 mm. Doing the calculation for you, a modern dime weighs almost ten times (!) as much as a Charles I halfpenny.

How much was a halfpenny worth in 1625? In short, I'd describe it as the dollar bill of its day.

In England, one penny could buy a penny loaf of bread, the weight of which was regulated by law. In Sheppard and Newton's The Story of Bread (1957), a loaf weighing 4 pounds would have cost 5 pennies in London in 1625. These days, a loaf sold in a grocery aisle usually weighs around 1 pound, so putting things into a modern context, a single 1625 penny was capable of buying one modern-day loaf of bread, and so a halfpenny was worth half a modern-day loaf. Given that a loaf currently retails at Walmart for around US$2 to US$2.50, that means a halfpenny was equivalent to a dollar bill, give or take.

As the dollar bill of its day, a halfpenny would have served a crucial role in England's day-to-day commerce. But being so delicate, it must have done a poor job of it. Even worse would have been the silver farthing, England's smallest coin, worth a quarter-penny, or half a halfpenny. "A still more egregious case [of too small coins] was that of the silver farthings the Royal Mint issued in 1464. Weighing only three troy grains each, these were 'lost almost as fast as they were coined,'" writes George Selgin in Good Money.

How to solve silver's inability to serve as a good medium for lower-denomination coinage? Here's one of the attempts made by the minting authorities:

Halfpenny of King James II, 1687. Source: Yale University Art Gallery

This James II halfpenny is what is called token coinage. Minted out of tin, which had a very low value, a token coin such as this one was worth far more than the amount of tin residing in it. What gave it its value isn't the metal within, but James II's promise to repurchase the coin at its stipulated rate of a half-penny's worth of silver.

Unlike Charles I's feather-light 0.3 gram halfpenny, James II's halfpenny had some heft to it. Weighing in at 10.11 g, which is equal to two modern American quarters, there was no losing track of this beast. The tin halfpenny would certainly have served as a more durable dollar bill of its day than a Charles I silver halfpenny.

Alas, while tokens such as James II's tin halfpennies solve the too-small problem, they introduce a new problem: counterfeiting. Because the amount of metal in a halfpenny was so cheap relative to the face value of the halfpenny, it would have been very profitable for fraudsters to manufacture fakes. Which is indeed what happened. By the middle of the 18th century, close to half of all the farthings and halfpennies, all of which were token coins by then, were counterfeits, according to Selgin (pg 20).

To counter the counterfeiters, James II's 1687 halfpennies have a strange feature on them: a small copper plug. In the image above this plug has fallen out, but this link illustrates what a complete coin would have looked like. By adding a plug to the coin, mint officials were trying to increase the complexity and thus the cost of manufacturing fakes, thus reducing their attractiveness to fraudsters. In concept, we can think of these plugged halfpennies as a clumsy predecessor to Canada's toonie, which has a nickel outer rim and an aluminum-bronze central plug.

Alas, James II's tin halfpennies never worked out. The tin was quick to erode and the copper plug was prone to falling out. If the solution to silver's lower limit was to make token coinage, better to manufacture those tokens out of a tougher substrate like copper. By the 1690s, England's tin halfpenny experiment had ended.

Gold regulators

While our modern monetary system certainly has plenty of detractors, one of its successes is that we no longer need the services of the local gold regulator. In the late 1700s, the job of a gold regulator was to assay gold coins to determine if they were of the appropriate weight and fineness, modifying (ie 'regulating') the coin if necessary. When he was done, the gold regulator stamped the coin with his seal of approval and put it back into circulation.

The job of regulating coins may seem strange to us. But it was an ingenious way to cope with the lack of standardization that bedeviled monetary systems in the 1600 and 1700s, particularly in the colonies. There was no domestic supply of coins in North America back then, so settlers relied on a bewildering array of foreign coins as their media of exchange, each with its own weight and fineness, and most of poor quality. This included not only silver coins such as Spanish dollars, pistareens, and English crowns, but also a gamut of gold coins including Portuguese joes and moidores, English guineas, French Louis d'ors and pistoles, German carolines, and Spanish doubloons.

Each of these foreign gold coins was minted with a unique quantity of the yellow metal. For instance, the popular Portuguese half Johannes, or "half Joe", weighed 221 grains and was 91.7% pure when it left the mint, whereas a full-bodied Spanish doubloon weighed 416 grains (one gram equals ~15 grains). Thanks to constant wear and illegal clipping, these coins would inevitably lose some of their mass as they circulated. For merchants, the task of weighing each gold coin that was presented to them, checking if it was a counterfeit, and calculating its appropriate monetary value would have been fatiguing.

To help merchants determine the rate at which to accept a particular gold coin, the authorities published tables with coin weights and values. These coin standards were issued by various legislative bodies or by the merchants themselves. For instance, here is a table produced by the New York Chamber of Commerce in 1770:

Let's go through an example of how an American merchant might use this table. Say a customer offers a merchant a slightly worn half-Joe. The merchant measures the coin and discovers that it weighs exactly 9 dwt, or 216 grains. A dwt is a pennyweight, an archaic unit for measuring weights that derives from denarius weight. (1 dwt = 24 grains = 1.55 grams). Let's further assume say this exchange occurred in New York.

According to the above table, any half-Joe passed in New York that weighs at least 9 dwt 0 grains is legal tender for £3 and 4 shillings. Look in the columns titled "least weight" and "N. York". So if our merchant happens to be selling horses for £3 4s, then he'd be happy to accept the customer's slightly worn half-Joe as sufficient payment for a horse. But if the half-joe were to weigh less than 216 grains (or 9 dwt), then it would fail to meet the Chamber of Commerce's standards, and therefore the merchant wouldn't accept it—the coin is worth less than the horse's sticker price of £3 and 4 shillings.

Testing a coin's weight is easy, but it is unlikely that many merchants would have had the time or expertise to verify its purity. Whereas a Portuguese half-joe was minted with 91.7% fine, a good counterfeit half-joe might be just 88% pure. If a subsequent trading partner questioned a counterfeit's validity, a merchant who had accidentally accepted it could be out of pocket. To remove any doubt, a suspect coin could be brought to the local regulator to be assayed. After removing a small section of the coin, the regulator would then test the coin's gold content. If it was a good coin, he would plug up the test section and stamp his initials on it. Having been approved by a recognized member of the community, the coin could easily pass in trade.

This watchdog function reminds me of the part played by Chinese shroffs, or money changers, in the Chinese monetary system of the 17th-19th centuries. Like North America, China was inundated with a whole range of foreign coins. Local shroffs would assay a foreign coin to verify its silver content. If the coin passed their purity test, a shroff would stamp it with his own peculiar chopmark, usually a Chinese character or symbol. Over time, foreign coins circulating in China might collect multiple chops. The genius of this system is that a naive Chinese consumer could safely accept a strange coin knowing that it had successfully passed the smell test of professional appraisers—and the more chops the better.

Chopmarked 1807 Spanish silver dollar 

If you are interested in the Chinese practice of chopmarking, I wrote about it here and here.

Testing for fineness is just one theory for the role played by North American gold regulators. There is a second theory. Not only were they watchdogs, but regulators also acted as enhancers or correctors. To see why this might be true, let's delve a bit more into the dynamics in play in North America in the 1700s.   

If you look at the original table above, notice that the New York Chamber of Commerce listed the minimum accepted weight of the half-Joe as 216 grains. However, as I pointed out earlier, a freshly-minted half-Joe actually weighed 221 grains. So the Chamber of Commerce's standard tolerated the circulation of underweight half-Joes. (They did the same with other coins too, including the doubloon, which when freshly minted weighed 418 grains but was accepted by the Chamber of Commerce at 408 grains.) Providing some extra leeway was probably a wise move. The coins used by New Yorkers came from distant realms and inevitably suffered from wear & tear.

But if a half-joe had lost too much of it original heft it would fail to meet the Chamber's standard. This is where a gold regulator might come in handy. Say that a half-Joe was brought to a bank but found to only weigh 207 grains, well below both the Chamber's standard of 216 grains and its original mint weight of 221 grains. The bank would purchase it at discount, say by crediting the customer with just £3 1 shilling instead of the Chamber's standard £3 4s, then send the underweight coin to a gold regulator. The regulator would proceed to cut out a section of the coin and insert a purer (and heavier) gold plug into the hole, bringing its weight back up to the 216 grain standard.

The regulator would then stamp his initials on his modification, upon which the bank would pay the regulated coin out as change. The regulator's marks were proof that the coin lived up to the Chamber's weight standard, and presumably made it easier to pass from hand to hand. Here is what a coin that has been regulated with a plug looks like:

In the 1700s, only foreign gold coins circulated in the US. The job of a "regulator" was to weigh each one. If it was underweight relative to the standard, they added a plug and initialed it (like the one below, countermarked by John Bayley). If it was overweight, the shaved it. pic.twitter.com/JfRXKq20DP

— JP Koning (@jp_koning) May 14, 2018

The coin in my tweet is a regulated 1747 Portuguese half-Joe. Notice that the plug is slightly raised on the face side of the coin, or the obverse side. On the reverse side of the coin, the plug is rounded and convex. So it apparent to the eye how the plug might add some heft to an underweight coin.

A coin could also be modified in a way that reduced it to the Chamber's standard. If a fresh half-Joe arrived in New York weighing 221 grains, it made no sense for its owner to spend it as-is. Given the Chamber's standards, a 216 grain half-Joe was sufficient to buy £3 and 4 shillings of goods and services (or settle £3 and 4 shillings debts). A 221 grain half-Joe was overkill. A customer could deposit their full-weighted half-joe at the bank for more then its value (say £3 and 5 shillings). The bank's gold regulator would then shave it down to size and stamp his initials on it. Thus the modified half-joe could circulate legally despite having a small amount clipped from it. It would have looked a bit like this:

Regulated 1774 Portuguese half-joe. Source

Note the flat part at the bottom where the half-Joe has been clipped by a regulator.

So a gold regulator's role, whether it be as a watchdog or an enhancer, or a bit of both, was to bring some much-needed order to the chaos of a multicoin monetary system. By bringing a gold coin up to standard, or reducing it to standard, they would have helped ensure the fungibility of North America's coinage. And by stamping their initials on it, regulators provided a guarantee of purity to the public—removing some of the uncertainty involved in accepting unfamiliar coins.

By the 1800s, there was no longer a need to have a gold regulators. Most of the deficiencies of the old non-standardized monetary system had been fixed. Paper money had largely displaced gold coins, so merchants had fewer occasions where they had to worry about accepting bad coins. As for smaller denomination silver coins, these were eventually replaced by token coins. The issuer's promise to buy them back at a fixed price, and not their metal content, dictates a token's value. While their time may be past, gold regulators remain a testament to monetary ingenuity.

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Selected sources:
1. Sedwick, Daniel: The Regulated Gold Coinage of North America and the West Indies in the Late 1700s [link]
2. Michener, Ron: Money in the American Colonies [link]
3. Neufeld, EP: Money and Banking in Canada
4. The Yale University Brasher Doubloon [link]
5. Introductory Note: Report on the Establishment of a Mint, [28 January 1791] [link]
6. Mossman, Phillip: Money of the American Colonies and Confederation [link]

You call that counterfeiting? This is counterfeiting!

One of the world's most notorious cases of counterfeiting was the 1925 Portuguese banknote crisis, when Artur Virgilio Alves Reis managed to pass off 200,000 fake five-hundred escudo notes, worth around £56 million in 2016 terms. When the Bank of Portugal discovered the counterfeits in December 1925, it announced an aggressive demonetization of the five-hundred escudo note, giving citizens just twenty days to bring in old notes for redemption. By then, the damage had been done. Reis had managed to increase Portugal's supply of banknotes by 5.9%, spending the equivalent of 0.88% of Portugal's nominal GDP into circulation! (More here.)

An aggressive note demonetization in the face of large-scale counterfeiting is a thoroughly justified response as it immediately puts a halt to the problem. In this context, it's worth revisiting the world's most recent attempt to combat counterfeiting with an aggressive demonetization—India PM Narendra Modi's forced recall of the Rs1000 and 500 notes on November 9, 2016, some 290 days ago. How does it compare to Portugal in 1925?

If we go back to Modi's initial speech, India's demonetization was targeted at the three "festering sores" of corruption, black money, and terrorism. On the latter, Modi said:

Terrorism is a frightening threat. So many have lost their lives because of it. But have you ever thought about how these terrorists get their money? Enemies from across the border run their operations using fake currency notes. This has been going on for years. Many times, those using fake 500 and 1,000 rupee notes have been caught and many such notes have been seized.

Given Modi's fighting words, we'd expect the demonetization to have caught quite a bit of bad currency. Last month, finance minister Arun Jaitley revealed how many counterfeit notes had been detected:

Source

Translating Rs11.23 crore into dollar terms, the monetary authorities have found just US$1.7 million worth of counterfeit notes. Step back for a moment and compare $1.7 million to the full breadth and width of the demonetization. In declaring that all Rs1000 and 500 notes were to be useless, Modi  demonetized US$240 billion worth of paper rupees, around 85% of India's stock of banknotes. So only 0.001% of the entire face value that has been brought in for conversion was fake! That's an incredibly low value of counterfeits, especially when you consider that in 1925, Reis's counterfeits accounted for around 5% of the entire Portuguese paper money supply. 

Central bankers usually measure counterfeiting in parts per million, or PPM, the number of fakes detected in one year for every one million genuine notes in circulation. I've inserted a chart below, which comes from this Reserve Bank of Australia document. Canada, for instance, once had a much higher PPM (it even hit 450 back in 2004), but the Bank of Canada managed to bring this down to the low double digits by introducing new security features and, later, polymer notes.

Australia, the first nation to introduce polymer notes in the early 1990s, used to boast one of the lowest incidences of counterfeiting (below 5 PPM). Criminals are finally starting to make polymer fakes, perhaps because the RBA hasn't bothered to update the series for over two decades, giving plenty of time for counterfeiters to catch up.

In India's case, the recent numbers show a total of 158,000 fake notes detected (out of a 24 billion banknotes demonetized) between November 8, 2016 and July 14, 2017, this totaling up to a minuscule 6.6 PPM—in the same range of countries like Canada or Australia. And certainly not in the same category as Portugal in 1925.

Nor is this data anomalous. Back in January, James Wilson—an Indian civil engineer-turned-demonetization expert—perused official banknote statistics only to find that over the last few years India has not had a high incidence of counterfeit rupees, leading him to describe the demonetization effort as a cannon shooting at sparrows. Using some of the data from James' post, it's possible to calculate that India had a PPM of 7.1 in 2015/16. (I get this from 90.266 billion units of currency in circulation, and 632,926 counterfeits detected that year). This is consistent with earlier data from the Reserve Bank of India showing a PPM from 2007-2012 ranging between 4.4 to 8.1. So India's rate of counterfeits detected is fairly reasonable relative to other countries.

This low PPM could be due to two factors. Either India doesn't have a counterfeiting problem, or it does have one but the authorities are just really bad at detecting counterfeits. If neither Indian banks nor its central bank are particularly good at identifying fake notes, then a large stock of unidentified fakes may be permanently circulating along with legitimate banknotes with no one capable of draining out the fakes. But even so, why instigate a massive note recall to catch counterfeits if the institutions that do the catching are so leaky to start with? If it is the case that India has a counterfeiting problem, then Modi's go-to fixes should have been to improve note security features and the banking system's ability to detect fakes, not implement a massive Portuguese-style recall.

So the data certainly destroys one of the pillars on which Modi's demonetization was based; terrorism and fake currency. You need something like a Portugal in 1925 to justify an aggressive demonetization, and India wasn't even close. Over the next few months more data will pour in, expect Modi's scheme to be further tested.

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P.S. The title is cribbed from here:

Chain splits under a Bitcoin monetary standard

The recent bitcoin chain split got me thinking again about bitcoin-as-money, specifically as a unit of account. If bitcoin were to serve as a major pricing unit for commerce on the internet, we'd have to get used to some very strange macroeconomic effects every time a chain split occurred. In this post I investigate what this would look like.

While true believers claim that bitcoin's destiny is to replace the U.S. dollar, bitcoin has a long way to go. For one, it hasn't yet become a generally-accepted medium of exchange. People who own it are too afraid to spend it lest they miss out on the next boom in its price, and would-be recipients are too shy to accept it given its incredible volatility. So usage of bitcoin has been confined to a very narrow range of transactions.

But let's say that down the road bitcoin does become a generally-accepted medium of exchange. The next stage to becoming a full fledged currency like the U.S. dollar involves becoming a unit of account—and here things get down right odd.

A unit of account is the sign, or unit, used to express prices. When merchants set prices in a given unit of account, they tend to keep these prices sticky for a while. A few of the world's major units of account include the $, £, €, and ¥. These units of account are conventional ones because there is an underlying physical or digital token that represents them. The $, for instance, is twinned with a set of paper banknotes issued by the Federal Reserve, while ¥ is defined by the Bank of Japan's paper media. Unconventional units of account do not have underlying tokens, but I'll get to these later.

So let's go ahead and imagine that bitcoin had succeeded in becoming the unit of account on the internet. The most commonly heard complaint of bitcoin-as-unit of account—a bitcoin standard so to say—is that it would be inflexible, more so than even the gold standard. It would certainly be more volatile, since the supply of bitcoin—unlike gold—can't be increased in response to prices. And those are fair criticisms. But there's a less-talked about drawback of a bitcoin standard: when a chain split occurs, all sorts of confusing things begin to happen that wouldn't occur in a conventional monetary system.

For those not following the cryptocurrency market, a chain split is when a new cryptocurrency is created by piggy-backing off an existing cryptocurrency's record of transactions, or blockchain, thus creating two blockchains. Luckily for us, a bitcoin chain split occurred earlier this month and provides us with some grist for our analytical mill. On August 1, 2017 anyone who owned some bitcoins suddenly found that not only did they own the same quantity of bitcoins as they did on July 31, but they had been gifted an equal number of "bonus" tokens called Bitcoin Cash, henceforth BCH. Both cryptocurrencies share the same transaction history up till July 31, but all subsequent blocks of transaction added since then have been unique to each chain.

This doesn't seem to be a one-off event. Having just passed through a split this August it is likely that Bitcoin will undergo another one in November. The history of Bitcoin is starting to resemble that of Christianity; a series of contentious schisms leading to new offshoots, more schisms, and more offshoots:

Source

Here's the problem with chain splits. Say that you are a retailer who sells Toyotas using bitcoin, or BTC, as your unit of account. You set your price at 10 BTC. And then a chain split occurs. Now everyone who comes into your shop holds not only x BTC but also x units of Bitcoin Cash. How will your set your prices post-split?

The most interesting thing here is that an old bitcoin is not the same thing as a new bitcoin. Old bitcoins contained the entire value of Bitcoin Cash in them. After all, the August 1st chain split was telegraphed many months ahead—so everyone who held a few bitcoins knew well in advance that they would be getting a bonus of Bitcoin Cash. Because a pre-split price for the soon-to-be tokens of $300ish had been established in a futures market, people even knew the approximate value of that bonus. This anticipated value would have been "baked into" the current price of bitcoins, as Jian Li explain here. Then, once the split had occurred and Bitcoin Cash had officially diverged from the parent Bitcoin chain, the price of bitcoins would have fallen since they no longer contained an implicit right to get new Bitcoin Cash tokens. 

Thus, BTCa = BTCb + BCH, or old bitcoins equals the combined value of new bitcoins and Bitcoin Cash.*

As a Toyota salesperson, you'd want to preserve your margins throughout the entire splitting process. In the post-split world, if you continue to accept 10 BTC per Toyota you'll actually be making less than before. After all, if one BTC is worth ten BCH in the market, then a post-split bitcoin—which is no longer impregnated with a unit of BCH—is worth just nine-tenths of a pre-split bitcoin. In real terms, your income is 10% less than what is was pre-split.

You have two options for maintaining your relative position. Option A is to continue to price in current BTC, but jack up your sticker price by 10% to 11 BTC. Customers will now owe you more bitcoins per Toyota, but this only counterbalances the fact that the bitcoins you're getting no longer have valuable BCH baked into them.

This would make for quite an odd monetary system relative to the one we have now. If everyone does the same thing that you do—mark up their sticker prices the moment a split occurs—the economy-wide consumer price level will experience a one-time shot of inflation. Given that bitcoin schisms will probably occur every few years or so, the long-term price level would be characterized by a series of sudden price bursts, the size depending on how valuable the new token is. When splits are extremely contentious, and the new token is worth just a shade less than the existing bitcoin token, the price level will have to double overnight. That's quite an adjustment!

We don't get these sorts of inflationary spasms in modern monetary systems because there is no precise analogy to a chain split. When August 1st rolled around, Bitcoin supporters could not invoke a set of laws to prevent Bitcoin Cash from being created on top of the legacy blockchain. In fiat land, however, a set of actors cannot simply "fork" the Canadian dollar or the Chinese yuan and get off scot-free. The authorities will invoke anti-counterfeiting laws, which come with very heavy jail sentences.**

The closest we get to chain splits in the real world are when the monetary authorities decide to undergo note redenominations. Central bankers in economies experiencing high inflation will sometimes call in—say—all $1,000,000 banknotes and replace them with $10 banknotes. And to compensate for this lopping-off of zeroes, merchants will chop price by 99.999% overnight. But redenominations are very rare, especially in developed countries. Up until it dollarized in 2008, even Zimbabwe only experienced three of them. Under a bitcoin standard, they'd be regular events.

Option B for preserving your relative position is to keep a sticker price of 10 per Toyota, but to update your shop's policy to indicate that your unit of account is BTCa, or old bitcoin, not new bitcoin. Old bitcoin is just an abstract concept, an idea. After all, with the split having been completed, bitcoins with BCH "baked in" do not actually exist anymore. But an implicit old bitcoin price can still be inferred from market exchange rates. When a customer wants to buy a Toyota, they will have to look up the exchange rate between BTCa and new bitcoin (i.e BTCb), and then offer to pay the correct amount of BTCb.

To buy a Toyota that is priced at 10 BTCa, your customer will have to transfer you 10 new bitcoins plus the market value of ten BCH tokens (i.e. 1 bitcoin), for a total price of 11 bitcoins. This effectively synthesizes the amount you would have received pre-split. As the market price of Bitcoin Cash ebbs and flows, your BTCa sticker price stays constant—but your customer will have to pay you either more or less BTCb to settle the deal.

The idea of adopting a unit of account that has no underlying physical or digital token might sound odd, but it isn't without precedent. As I pointed out earlier in this post, our world is characterized by both conventional units of account like the yen or euro and unconventional units of account. Take the Haitian dollar, which is used by Haitians to communicate prices. There is no underlying Haitian dollar monetary instrument. Once a Haitian merchant and her customer have decided on the Haitian dollar price for something, they settle the exchange using an entirely different instrument, the Haitian gourde. The gourde is an actual monetary instrument issued by the nation's central bank that comes in the form of banknotes and coins.***

So in Haiti, the nation's unit of account—the Haitian dollar—and its medium of exchange—the gourde—have effectively been separated from each other. (In my recent post on Dictionary Money, I spotlighted some other examples of this phenomenon.) An even better example of separation between medium and unit is medieval ghost money. According to John Munro (link below), a ghost money was a "once highly favoured coin of the past that no longer circulated." Because these ghost monies had an unchanging amount of gold in them, people preferred to set prices in them rather than new, and lighter, coins, even though the ghost coins had long since ceased to exist.

I love the medieval concept of ghost money: using a long dead coin—say Louis IX's gros tournois—as a unit of account https://t.co/TmCTE7OdBs pic.twitter.com/LUNntsw0l3

— JP Koning (@jp_koning) August 22, 2017

Unlike option A, which would be characterized by a series of inflationary blips each time a split occurred, option B provides a relatively flat price level over time. After all, the old bitcoin price of goods and services stays constant through each split. However, as the series of chain splits grows, the calculation for determining the amount of new bitcoins inherent in an old bitcoin would get lengthier. In the example above, I showed how to calculate how many bitcoins to use after just one chain split. But after ten or eleven splits, that calculation gets downright cumbersome.

Whether option A or B is adopted, or some mish-mash of the two, a bitcoin standard would be an awkward thing, the economy being thrown into an uproar every time a chain schism occurs as millions of economic actors madly reformat their sticker prices in order to preserve the real value of payments. If bitcoin is to take its place as money, it is likely that it will have to cede the vital unit of account function to good old non-splittable U.S. dollars, yen, and other central bank fiat units. The Bitcoin community is just too sectarian to be trusted with the task of ensuring that the ruler we all use for measuring prices stays more or less steady.

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P.S.: I've focusing on sticker prices here, I haven't even touched on contracts denominated in bitcoin units of account. For instance, if I pay 10 BTC per month in rent for my apartment, what do I owe after a split? Ten old bitcoins? Ten new bitcoins? Or would I have to transfer 10 new bitcoin along with 10 units of Bitcoin Cash? Who determines this? What about salaries? The problem of contracts isn't merely theoretical, it actually popped up in the recent split as some confusion emerged on how to deal with to bitcoin-denominated debts used to fund short sales. Matt Levine investigated this here. 


*There is also the complicating fact that the price of bitcoin didn't seem to fall by the price of Bitcoin Cash, thus contradicting the formula. As Matt Levine recounts:

In a spinoff, you'd expect the original company's value to drop by roughly the value of the spun-off company, which after all it doesn't own any more. 5  BCH spun off from BTC on Tuesday afternoon, and briefly traded over $700 on Wednesday (though it later fell significantly). But BTC hasn't really lost any value since the spinoff, still trading at about $2,700. So just before the spinoff, if you had a bitcoin, you had a bitcoin worth about $2,700. Now, you have a BTC worth about $2,700, and also a BCH worth as much as $700. It's weird free money, if you owned bitcoins yesterday.

**Say counterfeiters do manage to create a large amount of fakes. Even then this "fiat split" would have no effect on the value of genuine notes. Central bank are obligated to uphold the purchasing power of their note issue. They will filter out fakes be refusing to repurchase them with assets, the purchasing power of counterfeits quickly falling to zero, or at least to a large discount. When central banks are fooled by counterfeits they will use up their stock of assets as they erroneously repurchase fakes. But even then they will never lose the ability to uphold the value of banknotes as long as the government backs them up with transfers of tax revenues. Fiat chain splits only begin to have the same sort of effects as bitcoin chain splits when 1) counterfeiting goes unpunished; 2) the central bank can't tell the difference between which notes are genuine and which are fakes; and 3) it lacks the firepower and government support necessary to buy back paper money in sufficient quantity. Only at this point will counterfeiters succeed in driving the economy's price level higher.

This, by the way, is what the Somali shilling looks like... a fiat currency constantly undergoing chain splits. 

*** I get my information on Haiti from this excellent paper by Frederico Neiburg.

The dematerialization of cash

"One dollar bill," watercolour by Adam Lister (source)

R3, a company specializing in distributed ledger technology, has just posted a paper I wrote for them entitled Fedcoin: A Central Bank-issued Cryptocurrency. And here is a nice write-up on the Fedcoin idea in American Banker, which unfortunately is behind their paywall.

The paper is pretty wide-ranging, but one thing that's worth focusing on is the ability of Fedcoin to provide some of the same features as banknotes, in particular anonymity and censorship resistance. That a Fedcoin system can be designed to provide the same degree of privacy as cash runs counter to some of its early critics, who see in Fedcoin a coming financial panopticon.

One really neat things about good ol' cash is that, like bitcoin, it is a decentralized network. The opposite of this is a centralized network, say something like the deposit banking system. In the banking system, storage of value is handled by the issuing bank through accounts hosted on the bank's database. Conversely, in a banknote system, the issuing central bank offloads the task of storing value onto us. We the public—think of us as nodes in a decentralized network—are responsible for choosing how and where to keep our cash, say in a wallet, or under our bed, or in a safety deposit box, as well as bearing those storage costs. The central bank doesn't care how we manage this task, though they'd prefer that we don't mangle the notes too much.

Or take the process of securely transferring value. Centralized actors like banks handle all the stages of moving deposits from a buyer to a seller, including verifying identities, ensuring adequate account balances, updating ledger entries etc. But in a transfer of banknotes, the transaction process is entirely devolved to the buyer and seller, who must physically move the cash to the right location, count out by hand the necessary quantity of banknotes, and then come to a consensus that the transaction has been settled. As for the central bank's ledger of notes, there is nothing that needs updating. Unlike private bankers, central bankers don't care who owns their circulating liabilities.

The task of screening for counterfeit notes is also outsourced to the public. Each time a shopper accepts a banknote, say as change, they'll give it a once-over to verify that it hasn't been run off by a teenager using an inkjet printer. Retailers deal in cash all day and are familiar with banknote anti-counterfeiting devices, and thus can exercise more judgement in checking for fakes. And banks, the recipient of notes from retailers at the end of the day, will catch many of the counterfeits that have slipped through the system.

Banknote systems aren't entirely decentralized, of course. The central bank has the final say on whether a note is counterfeit or not. It also regulates the purchasing power of those banknotes, either by toggling interest rates higher or lower, repurchasing money using its portfolio of assets, or issuing more money in return for assets.

Because they are at least partly decentralized, banknote systems inherit two nice features: anonymity and censorship resistance. The first feature is self-explanatory: the central issuer makes no effort to determine the identity of a banknote owner. Proceeding from this, the issuer lacks enough information to censor, or prevent any particular party, from using the banknote network. These are completely open systems. By contrast, centralized systems like banks can easily censor members of the public from making payments. Take the Huntingdon Live Sciences episode in 2001, for instance, in which a UK-based company involved in drug-testing was cut off by British banks in response to pressure from animal rights activists. Other examples of censorship by banks include the blockade of Wikileaks and the monetary embargo of Iran.

Now in theory a banknote system could be modified by introducing more centralization, thus removing anonymity and introducing censorship. Each banknote has a unique serial number. The central bank could set a rule that for every cash transaction, the buyer and seller are obligated to log in to a government-provided account where they register the note's serial number into a tracking database. To get these accounts, users would be required to submit documents and ID. This would destroy the anonymity of cash users and open the door for censorship. In practice, though, the guardians of banknote systems have chosen to preserve anonymity by ignoring serial numbers.

One of the major trends over the last decades has been dematerialization, the replacement of paper by bits and bytes as a medium for holding data. This saves on costs like printing, storage, and distribution; improves speed; and reduces waste. We saw it with stock & bond certificates a few decades ago, books, newspapers, music, record keeping, bills. And one day we may see it with cash. The question is: how to allow for the dematerialization of cash without losing its useful features like anonymity and censorship resistance?.

Bitcoin is one answer. But Bitcoin only goes half-way to solving the problem since it does not recreate one of cash's other key features, its stability. A nation's prices are conveniently denominated in terms of its paper money (i.e. U.S. retailers set prices in dollars, Japanese retailers in yen), and since prices tend to stay sticky for 4.3 months or so on average, the public has a huge degree of certainty over the medium-term purchasing power of the money in their wallets. This is a very nice feature. Bitcoin prices? Not so stable.

Fedcoin may be able to recreate this stability while still providing anonymity and censorship resistance. A government copies the source code of a proven cryptocoin (maybe bitcoin, maybe zcash, maybe ethereum), boots the system up, and promises to peg the price of each coin to its existing banknotes, say 1 coin = $1 banknote.

As with bitcoins, anyone would be able to hold Fedcoins without the necessity of providing identification. And like Bitcoin, Fedcoin could be designed in such a way that a distributed collection of Fedcoin nodes (or miners) validate transactions by referring to the system's shared history. Remember how the Fed allows banknote users to anonymously come to a consensus about the validity of a banknote transactions i.e. they do not have to log in to an account to register note serial numbers? Likewise, Fedcoin could be designed in a way that nodes have the ability to remain anonymous. This would preserve a degree of censorship resistance and openness. After all, if validators must unveil themselves, governments and other powerful actors might compel those nodes to censor transactions.

This is just one way of setting up anonymous central bank money. I'm sure there are many others. There are also ways to set up non-anonymous central bank money, but these are less interesting to me, a point I made here. As I point out in the R3 paper, I think my preferred set-up would be to allow individuals a rationed amount of anonymity, targeting some sort of “sweet spot” such that there is enough anonymity-providing exchange media for regular consumers but not enough for criminals. But I can't wrap my head around how to design something like this. Anyways, go read the paper, there's plenty more.

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PS: I also recently had an article on bitcoin published in the Common Reader, a publication of Washington University in St. Louis.

And since we're on the theme, I should link to some other public appearances by yours truly, including recent-ish podcasts with David Beckworth and Alex Millar.

What happens when a central bank splits in two?

Say the San Francisco Fed decided to secede from the Federal Reserve System or the Bank of Greece started to print its own euro notes without the consent of the Eurosystem. What happens to a nation's currency when the central bank is split into parts? There is a possibility we might be seeing such a situation developing in Libya with the emergence of two different Libyan dinars.

Libya's political scene is ridiculously complicated so I'll paint the picture in broad brush strokes. The Central Bank of Libya has several offices, the two relevant ones being the western one in Tripoli and the eastern one in Bayda. Prior to the Arab spring, each area was under the control of the Gaddafi government but both have since come under the control of competing regimes. Tripoli is run by the U.S.-backed Government of National Accord (GNA) while Bayda is under the control of the Tobruk-based House of Representatives.

As I understand it, over the last few years of strife the two offices have usually been able to work together despite being under different regimes.Yesterday, however, the Bayda branch announced that it would be putting new 20 and 50 dinar denomination notes into circulation. Both the Tripoli government and their U.S. backers quickly declared that the new issue was illegitimate. The U.S. Embassy's statement on Facebook said that "the United States concurs with the Presidency Council's view that such banknotes would be counterfeit and could undermine confidence in Libya's currency and the CBL's ability to manage monetary policy to enable economic recovery."

This brings up an interesting conundrum. Say the Bayda branch of the Central Bank of Libya starts to spend the new 'counterfeit' dinars and the U.S.-backed Tripoli branch refuses to recognize them. Will the public accept the new issue of Bayda dinars, and if so, at what rate will the notes trade relative to Tripoli's notes? Could Libya end up with two different dinar currencies?

Were the two note issues identical, it would be impossible for Libyans to discriminate between them. They'd happily accept the new notes and all dinars would continue to be fungible. But this doesn't seem to be the case. Unlike Libya's legacy note issue, which was printed by De La Rue in the U.K., the Bayda branch's new dinars are printed by Goznak in Russia. Apparently Goznak has used different watermarks and a horizontal serial number rather than a vertical one. Most importantly, the new notes bear the signature of the head of the Bayda office while the old notes have the Tripoli branch's chief on them.

If it does not recognize Bayda's 'counterfeit' notes as its liability, the Tripoli branch voids its responsibility to buy them back in order to maintain their value, effectively walling off its resources from the Bayda branch. These resources include any foreign reserves it might have, U.S. financial backing, and financial support from the local regime. And without any guarantee that those notes will have a positive value, the public—which can easily differentiate between the two bits of paper—may simply refuse to accept Bayda dinars at the outset when the Bayda branch tries to spend them into circulation. Long live the Tripoli dinar.

The Bayda branch might try to promote the introduction of Baydar dinars by pegging them at a 1:1 rate to existing Tripoli dinars. This is how the euro, for instance, was kickstarted. But that peg will be tested. Libyans will bring Bayda dinars to the Bayda branch to exchange for Tripoli dinars. If the branch runs out of Tripoli banknotes, it will have to buy more of them in the open market to maintain the peg, but with what? If it lacks the resources to buy them, the peg will be lost and Bayda dinars will fall to zero, or to a very large discount.

But the Bayda branch isn't without its own resources. First, it has the financial support of the local regime. Furthermore, according to this surreal article there is a vault in Bayda that contains 300,000 gold and silver sovereigns minted in honour of the late Colonel Gaddafi, worth nearly £125 million. The Bayda branch doesn't know the combination and Tripoli refuses to provide it. If the safecrackers that the Bayda branch has hired are able to get in, that amount will provide it with enough firepower to buy back Bayda dinars and help support the peg. In which case the two notes would circulate concurrently and be fungible.

If two dinars emerge, which central bank would control monetary policy? That depends on which brand of dinar Libyans choose to express prices and debts. As long as the existing Tripoli dinar is the medium of account—the physical object that people use as the definition of the dinar unit ل.د.—then any policy change adopted by Tripoli's central bankers will be transmitted to the entire Libyan price level, both the east and west. Usage of Tripoli dinars rather than Bayda dollars for pricing is likely to prevail for the same reason we all use QWERTY keyboards when better alternatives exist, force of habit is difficult to overcome. Even if Bayda dollars do emerge as a medium of account, as long as they are pegged to the Tripoli dollar, then Tripoli still gets to call the shots.

The situation isn't resolved yet—the Tripoli branch could very well accept Bayda dinars as its liability, thus defusing the situation. In any case, it will be interesting to follow. Incidentally, Libya's situation reminds me of one of the ideas put forth during the 2015 Greek crisis; a secession of the Bank of Greece from the Eurosystem so that Greeks could print their own type of euro. If Greece boils over again and the separation idea pops up, Libya may serve as a reference point.

Can a central bank eliminate its highest value banknote?

Singapore's $10,000 bill, worth around US$7500, shares title to world's largest value banknote with Brunei's $10,000

Peter Sands has adeptly made the case for eliminating high denomination banknotes. The rough idea is that if all central banks were to eliminate their highest value banknotes, then criminals would have to fall back on smaller denominations or more volatile media of exchange like gold. Since both of these options are more cumbersome than large denomination notes, storage and handling expenses will grow. This means the costs of running a criminal enterprise increases as does the odds of being apprehended.

Elimination of cash is a polarizing topic. For now I'm going to sidestep that debate because I think there's a more interesting topic to chew on: might a central bank be unsuccessful in its attempt to withdraw its own high denomination notes? Put differently, what happens if everyone just ignores a central banker's demands to retire the biggest bill?

Take the most popular high denomination banknote in the world, the US$100 bill. According to the Federal Reserve, there are 10.8 billion of these in circulation, or around $1 trillion in nominal value terms. Popular not only with criminals, the $100 bill circulates in many dollarized or semi-dollarized nations as a legitimate means of exchange in the absence of decent local alternatives. Say that the Federal Reserves wants to hobble criminals by cancelling all 10.8 billion notes. It announces that everyone holding $100s has until January 1, 2018 to trade them in for two $50s (or five $20s). After that date any $100 notes that remain in circulation will no longer be considered money. Specifically, they will cease to be recognized by the Fed as a liability.

Will this demonetization work? Consider what happens if everyone simply ignores the proclamation and continues to use $100s in trade. Say that by the January 1, 2018 expiry date, only $300 billion of the $1 trillion in $100 bills in circulation have been tendered leaving the remaining $700 billion (or 7 billion individual notes) in peoples' pockets.

So much for hurting criminals by removing the $100, right? We'd say that the central bank's demonetization campaign has failed. But not so fast.

Even though 7 billion $100 bills remain in circulation, the nature of $100 bill will have changed. Prior to January 1, 2018, the Fed maintained a peg between the $100 bill and all other denomination ($50, $20, $10, $5, and $1). This peg was enforced by the Fed's promise to convert any quantity of $100 bills into lower denominated notes and vice versa. After the expiry date, the Fed will no longer include the $100 in these pegging arrangements.

In addition to maintaining a fixed rate between the various denomination, the Fed also promises to peg the value of a dollar to a slowly-declining bundle of consumer goods (put differently, it set a 3% 2% inflation target). It does so by injecting an appropriate quantity of new currency into the economy via open market purchases or withdrawing sufficient currency by selling assets. When the Fed demonetizes the $100 note, it ceases to include the $100 in its consumer goods peg. This means it will no longer dedicate any of its assets to protecting the purchasing power of the $100 bill.

Given this new setup, as demand for $100 bills varies their value will float relative to both Fed dollars and the slowly declining consumer good bundle. Like bitcoin, which also has a fixed supply, fluctuations in the purchasing power of the $100 could be quite volatile. One day the $100 might be worth $110, the next it could be worth just $90. So even if the Fed has failed in withdrawing the $100, it will still have succeeded in imposing purchasing power volatility on criminals and other users of the $100. Volatile assets make for unpleasant and costly media of exchange and criminals will not be happy with these change.

By forswearing the $100, the Fed also ceases to act as a guardian of the quality of its issue of $100 bills against counterfeiters. The abdication of this function is especially important given that the marginal cost of printing a decent knock off of the $100 is probably just a few cents. Absent the threat of imprisonment, entrepreneurs will swarm to duplicate the $100, spending counterfeits into circulation and steadily reducing the purchasing power of the $100. After a few years of constant counterfeiting the $100 bill won't be worth much more than a few cents or so; the marginal cost of paper, ink, and printing. This hyperinflation will bring the nominal value of the original 7 billion in notes to just $700 million, down from $1 trillion.

Highest denomination note in various counties, sorted by US$ equivalent

Incidentally, we know this is a likely situation because of what has happened in Somalia. When Somalia's central bank was dismantled in the early 1990s, Somali shillings continued to circulate (see my blog post here). Over the next few years, warlords issued their own counterfeits which eventually drove the value of the shilling down to the cost of paper and transportation. William Luther has described this process here.

Along the way to hitting a terminal value of just a few cents, the $100 will lose any advantage it had previously enjoyed in terms of storage costs and handling. The moment a $100 falls to $49, the Fed's own $50 note becomes a cheaper note for criminals to use. And as the hyperinflation continues and the $100 falls to $19, the Fed's own $20 note will become preferred. The upshot is this: even if the Fed's January 1, 2018 expiry date fails to attract any $100s for redemption, competitive counterfeiting means that the $100 will inevitably cease to be used as the criminal economy's preferred medium of exchange.

Since criminals are rational and can anticipate that this sort of hyperinflation will ensue, they are more likely to tender their notes for cancellation prior to the original January 1, 2018 deadline. Better to get full restitution rather than lose all one's wealth.

Could criminals somehow police against hyperinflation by rejecting counterfeits? Militating against this would be the constant degradation of the note issue's quality due to normal passage of paper from hand to hand. In normal times, the Fed works behind the scenes to keep its note issue up to snuff, replacing worn out specimens with fresh new greenbacks. Once the Fed abdicates this role, $100 bills will quickly start to deteriorate. Picking the counterfeits out from a stack of bills will become more difficult, only making the job of counterfeiting easier.

In the face of this deterioration the mass of $100 bills may begin to fragment and lose fungibility. Fungibility is the idea that all members of a population are perfect substitutes. Well-preserved $100s that are easily identifiable as non-counterfeits may pass at a higher value than a slightly worn out $100, with well-worn and less identifiable $100 bills trading at an even larger discount. Without fungibility, it becomes far more difficult for a medium of exchange to do its job. Where a transaction with fungible $100 notes might be consummated in a few moments, it may take hours to grade a small stack of heterogeneous bills. The costs arising from non-fungibility may be so high that criminals will prefer to use relatively bulky $50 bills which, though possessing higher storage costs, will not be plagued by the requirement that each note be closely analyzed for quality.

So in the end, even if criminals ignore a central bank's deadline to tender notes for cancellation, they will eventually cease using the highest denomination notes through a more roundabout route. A central bank's renouncement of both its role as enforcer of the largest denomination's peg to other notes as well as its commitment to tend to that note's quality will set off forces that drive the purchasing power of those notes down to the cost of paper and ink, at which point they will be as good as demonetized.

Having settled whether a central bank can demonetize its highest value note, should it? That's an entirely different post. Or we can hash it out in the comments.

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PS. An alternative story to a Somali-style hyperinflation is an Iraqi-style deflation. See Tony Yates on Twitter. I've written about the odd case of the Iraqi Swiss dinar here. How likely is an Iraqi scenario? Criminals would have to assume that a future monetary authority, maybe even the Fed itself, reverts its decision and undertakes to adopt orphan $100 bills as a liability at a price consistent with their previous purchasing power. This would give $100 bills a fixed value in the present.

PPS. On the topic of altering the relationship between high denomination notes and other notes, see my posts on high value note embargoes.