The Haitian dollar

Haiti is home to a strange monetary phenomenon. Shopkeepers and merchants set prices in the Haitian dollar, but there is no actual thing as the Haitian dollar.

I've written before about an exotic type of unit-of-account known as an abstract unit of account. A nation's unit of account is the symbol used by its citizens and businesses to advertise and record prices. Here in Canada we use the $ while in a country like Japan people use the ¥. The national unit of account almost always corresponds to the national medium-of-exchange. In both Canada and Japan, the $ and the ¥ amounts advertised in shop aisles are embodied by physical dollar and yen banknotes and coins.

Abstract units of account, on the other hand, don't correspond to anything that exists. In the UK, for instance, race horse auctions are priced in guineas, a gold coin that hasn't been minted in over two centuries. The guinea is a ghost money, an accounting unit that according to John Munro is "calculated according to the precious metal content of some famous, once highly favoured coin of the past than no longer circulates."

There are some strange units of account out there. In the UK, race horse auctions are priced in guineas, a coin that hasn't been minted in over 200 years. Source: https://t.co/cGujWAmlO8 One guinea = Sterling £1.05 pic.twitter.com/vMv927yooU

— JP Koning (@jp_koning) January 29, 2019

Other examples of abstract units of account include include Chile's Unidad de Fomento, or UF, (which I wrote about here) and Angolan macutes (see here).

Like the guinea, the Haitian dollar is an abstract unit of account. I should warn you that I've never been to Haiti--all of this comes from what I've read in tourist guides, newspapers, Haitian blogs, and an academic paper on the topic from Federico Neiburg. But from what I understand, it is quite common for prices in Haiti to be set in a unit referred to as the 'Haitian dollar.' However, there is no corresponding Haitian dollar banknotes or coins. The U.S. dollar and the Haitian gourde, a currency managed by Haiti's central bank, circulate in Haiti and are used to consummate all payments. But the Haitian gourde is not the same as the Haitian dollar.

How does this work in practice? Say that a restaurant is selling sandwiches for fifteen Haitian dollars. Paying with Haitian dollars is impossible--they don't exist--so some other route must be taken to complete the deal. Haitians have spontaneously adopted a rule of thumb that the Haitian dollar is equal to five Haitian gourdes. So to pay for the sandwich, it will be necessary to hand over 75 gourdes (H$15 x 5$H/HG).

Here is a sign showing both Haitian dollar and Haitian gourde (HTG) prices. Source: Pawol Mwen blog

A certain degree of mental gymnastics is thus required of Haitians, since sticker prices must always be multiplied by five (to arrive at the gourde amount) and banknotes held in a wallet divided by five (to arrive at the Haitian dollar amount). For foreigners, this can be confusing, but for Haitians the motley of U.S. dollars, gourdes, and the Haitian dollar unit of account has become second nature. Says Nieburg:

"The adjective Haitian (aysien), as in dolà aysien, is only used when one of the participants in a transaction is foreign. Among Haitians, when people say dolà they always mean dolà aysien."

Nieburg provides some more colour by describing the monetary demographics of Port-au-Prince, Haiti's capital:

"...in the urban islands of foreigners scattered across various regions of the city, the US dollar predominates as a unit of account and means of payment in sectors such as the housing market, as well as in restaurants, hotels, night clubs, and supermarkets (which used to double as currency exchange bureaus) that cater for upper-class Haitians and the legion of ex-pats, relief workers, and consultants. As we move down the social scale, the US dollar begins to be used as a means of payment for transactions calculated in Haitian dollars. Lower down—where the majority of transactions are to be found—people calculate in Haitian dollars and pay in gourdes."

Where does the practice of using the Haitian dollar come from? I wasn't aware of this, but during WWI the U.S. invaded Haiti, occupying it till 1934. There was a strong German mercantile presence in Haiti and apparently the U.S. authorities feared that Germany might take over.

By 1918 the government's gourdes had become "so worn and torn" that a shortage of banknotes arose. As part of a 1919 U.S.-initiated monetary reform, all previous issues of gourdes were to be replaced by a new issue by the Banque Nationale de la Republique d'Haiti, which by then was owned and controlled by New York-based City Bank (and would eventually become Citigroup). The BNRH was granted a monopoly on banknote issuance, which meant that the Haitian government could no longer print its own currency.

The new banknotes were to be convertible into U.S. dollars at a rate of five gourdes to the dollar, a promise that the BNRH printed on the face of each bill, as the images below illustrate.

1919 one gourde note (source)

 

"This bill issued by the National Bank of the Republic of Haiti, under its concession contract and conforming with the agreement of May 2, 1919, is payable to the holder in legal money of the United States at the rate of five gourdes to the dollar upon presentation to the bank's office in Port-au-Prince or, after a delay, at its provincial branches."

Even after the U.S. occupation ended and City Bank sold the BNRH back to the Haitian government, the promise to redeem gourdes with U.S. dollars continued. This peg stretched right through the rule of "Papa Doc" Duvalier until the gourde was finally untethered from the dollar in the late 1980s.

So several generations of Haitians had become used to a five-to-one ratio between U.S. dollars and gourdes. Dividing a price by five in order to get the U.S. dollar price may have become such a standard piece of mental arithmetic that the practice continued into the 1990s and 21st century, even after the calculation's answer no longer corresponded to the correct U.S. dollar amount. The Haitian dollar may simply have been a placeholder that was invented in order to provide continuity for the age-old custom of dividing by five.

Since it was unpegged, the Haitian gourde has fallen consistently against the U.S. dollar, possibly contributing to the tradition of using the Haitian dollar unit. Quoting prices in Haitian dollars could be a non-violent way for Haitians to show their dissatisfaction with their government's finances. Or perhaps it is a marketing trick that Haitian merchants use to make their wares seem less cheap, sort of like how shopkeepers here in Canada often set prices at $4.99 instead of $5.00.   

According to Nieburg, the government has even tried to ban the practice of pricing in Haitian dollars. Intellectuals who support the measure have condemned the abstract unit as just "another sign of the country’s backwardness." But the attempt failed. Units of account are just a part of language. And language is very difficult to control.

The Haitian dollar is probably the best (and simplest) modern example I've ever run into of an abstract unit of account. For monetary enthusiasts like myself, it provides a great illustration of the many different functions packaged into the thing we call "money." These functions needn't be unified into one object or instrument. They can be split up, so that the instruments that we pass from hand to hand (or from phone to phone), the so-called medium-of-exchange, no longer correspond to the symbol used for pricing, the unit-of-account.

Nobel Prize winning economist Robert Shiller has written enthusiastically about so-called monetary separation. William Stanley Jevons's tabular standard, which was never implemented but has been considered by some to be the ideal monetary system, relies on a split between the medium-of-exchange and unit-of-account. Rather than being backwards, the sort of Haitian dollar standard that we see in modern Haiti could one day become the guiding principle of the monetary systems of the future.

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.

Angolan macutes: Imaginary money

Economists are sometimes guilty of misrepresenting real-world liquid objects as living examples of the abstract variables populating their favorite monetary model. A good example of this is the incorrect reliance on Yap stones to illustrate the idea of fiat money by economists as varying as Keynes, Milton Friedman and James Tobin. Whereas fiat money is intrinsically useless, inconvertible, and unbacked, Yap stones certainly aren't, the anthropological evidence revealing that the stones had cultural and religious significance apart from their monetary value.

Similar in concept is the story of the macute, a unit of account used in Angola hundreds of years ago. Much like the exotic Yap stone, the existence of the macute (or macoute) came to the attention of Western thinkers as trade and conquest revealed ever large parts of the globe. Montesquieu was one of the first to describe the macute, noting:

The negroes on the coast of Africa have a sign of value without money. It is a sign merely ideal, founded on the degree of esteem which they fix in their minds for all merchandise, in proportion to the need they have of it. A certain commodity or merchandise is worth three macoutes; another, six macoutes; another, ten macoutes; that is, as if they said simply three, six, and ten. The price is formed by a comparison of all merchandise with each other. They have therefore no particular money; but each kind of' merchandise is money to the other. - Montesquieu, Esprit des Lois, 1748

Montesquieu's macute was later picked up by Sir James Steuart, an 18th century economist ranked just a notch or two below Adam Smith:

That money, therefore, which constantly preserves an equal value, which poises itself, as it were, in a just equilibrium between the fluctuating proportion of the value of things, is the only permanent and equal scale, by which value can be measured.

Of this kind of money, and of the possibility of establishing it, we have two examples: the first, among one of the most knowing; the second, among the most ignorant nations of the world. The Bank of Amsterdam presents us with the one, the coast of Angola with the other.

The second example is found among the savages upon the African coast of Angola, where there is no real money known. The inhabitants there reckon by macoutes; and in some places this denomination is subdivided into decimals, called pieces. One macoute is equal to ten pieces. This is just a scale of equal parts for estimating the trucks they make. If a sheep, e. g. be worth 10, an ox may be worth 40, and a handful of gold dust 1000. - An Inquiry into the Principles of Political Oeconomy, 1767

To Steuart and Montesquieu, the macute was an example of "ideal" money of account. The term money-of-account refers to the economy's pricing sign, or unit-of-account. It could be pounds (£), yen (¥), or dollars ($). Some real good typically defines this unit. For instance, the $ is the unit used to record prices in the US. The real good that defines the $ is base money issued by the Federal Reserve. In medieval times, prices were recorded in terms of £/s/d, with silver pennies being the defining real item (the "link coin"). To put this in the lingo of the econ blogosphere, the real good that defines the unit of account is the medium of account, a term popularized by Scott Sumner.

James Steuart's ideal money of account was a unit that, somewhat unusually, had no underlying real good defining it. It was a purely abstract accounting unit. There were prices in Steuart's economy, but no medium of account. Presumably Angolans were to keep the macute scale in mind, much like they might have a good sense for how long a foot was, or how much liquid a litre might contain. But at least with litres or feet there was a standard to which one might refer back to, say a metre stick or a measuring cup. Since the macute had no physical representation, goes the theory, it could only ever exist in people's heads.

Steuart and many others in his day believed in the necessity of an invariable scale of value. What was important to Steuart was the relative prices of real goods, not the price of some superfluous intervening good who's only job was to provide a measuring stick. If the money-of-account was a gold coin, for instance, then the "smallest particle of either metal added to, or taken away from any coin" would cause the entire price level to rise, destroying the ability of coins to measure the value of things. This would create macroeconomic difficulties:

any thing which troubles or perplexes the ascertaining these changes of proportion by the means of a general, determinate and invariable scale, must be hurtful to trade, and a clog upon alienation. This trouble and perplexity is the infallible consequence of every vice in the policy of money or of coin.

Fixing the money of account to a coin rather than allowing it to have an independent and abstract value caused distributional unfairness, since the relative interests of debtors and creditors were now at the disposal of anyone who could reduce the quality of coin,

not only of workmen in the mint, of Jews who deal in money, of clippers and washers of coin, but they are also entirely at the mercy of Princes, who have the right of coinage, and who have frequently also the right of raising or debasing the standard of the coin, according as they find it most for their present and temporary interest.

To those like Steuart, the advantage to society of an imaginary accounting unit like the macute was that, unlike physical coin, no prince or money clipper could ever debase it. It existed safely in the collective imagination where it could not be damaged, and therefore trade would no longer be held hostage to a fluctuating price level.

This idea spread. Around the time of Steuart, A.R.J. Turgot would also write of the macute as a purely imaginary unit:

The Mandingo negroes, who carry on a trade for gold dust with the Arabian merchants, bring all their commodities to a fictitious scale, which both parties call macutes, so that they tell the merchants they will give so many macutes in gold. They value thus in macutes the merchandize they receive; and bargain with the merchants upon that valuation. - Reflections, 1766

Macutes-as-ideal-unit would go on to be upheld a century later by John Stuart Mill:

This advantage of having a common language in which values may be expressed, is, even by itself, so important, that some such mode of expressing and computing them would probably be used even if a pound or a shilling did not express any real thing, but a mere unit of calculation. It is said that there are African tribes in which this somewhat artificial contrivance actually prevails. They calculate the value of things in a sort of money of account, called macutes. They say one thing is worth ten macutes, another fifteen, another twenty. There is no real thing called a macute: it is a conventional unit, for the more convenient comparison of things with one another. - Principles of Political Economy, 1848

As lovely as the idea of an imaginary macute was, it simply wasn't true. The macute was not so abstract as Montesquieu, Steuart, Turgot, and Mill would have liked it to be. William Stanley Jevons, for instance, scolded Montesquieu for misunderstanding the nature of money of account, since macutes served as "the name for a definite, though probably a variable, number of cowry shells, the number being at one time 2000." Lord Lauderdale accused Steuart of ignorance, noting that macutes were "pieces of net-work, used by the people of Angola for a covering." Like Lauderdale, John Ramsay McCulloch also found macutes to be bits of valuable cloth. Other writers declared that slaves were the missing medium-of-account used to describe the macute.

With the benefit of modern ethnographic accounts, we know that McCulloch and Lauderdale were right—macutes were neither imaginary, nor slaves, nor cowries, but cloth. In Power, Cloth and Currency on the Loango Coast, Phyllis Martin describes a coastal economy in which domestically produced cloth currency circulated. These libongo (pl. mbongo) were fourteen inch square pieces of cloth about the size of a hankerchief (see photo below). Mbongo had multiple uses. Not only could it be used in local markets to buy food and other consumption goods, but it could be made into clothes, wall hangings, bags, and floor coverings, and used for ceremonial purposes.

Kongo or Angola cloth, 17th century, raffia pile (source)

Martin also describes a traditional unit of account called a makuta (macute), defined as ten mbongo wrapped together in a strip. European trade brought foreign substitute cloth, and with that a decline in the purchasing power of the makuta, or inflation, resulted. As a result, copper coins came into increased use, although Martin finds that mbongo remained in circulation well into the eighteenth century. By the 1700s, around the time that Montesquieu was writing, the nature of the makuta unit of account had changed:

At Loango Bay traders used an abstract numerical unit of account based on a makuta, one mukuta being equal to 10. The unit may have developed from the older association of the mukuta with ten mbongo. Thus a slave-trader at Loango in 1701 wrote, "we bought men slaves from 3,600-4,000, and women, boys and girls in proportion." The goods to be exchanged were also valued in the numerical unit of account for example, a piece of "blue baft" or cotton cloth from India counted as 1,000, a piece of painted calico was 600, a small keg of powder was 300, and a gun was 300.40 

- Martin, Power, Cloth and Currency on the Loango Coast, 1986

What we have here is an example of "ghost money", not ideal money. An ideal money, having been divorced from any traded good, would have no commodity definition whatsoever. The mukuta (macoute) as described by Martin, however, was defined as a historically fixed, or "ghost" quantity, of mbongo. Though no longer prized as a highly liquid medium of exchange—copper coinage would have filled this place—mbongo were still desired for their non-monetary qualities. Thus any alteration in the real value of mbongo would continue to have an effect on all prices. It may have been this historically fixed "ghost" nature of macutes and their relative rarity in actual trade that confused Montesquieu into describing them as an ideal accounting unit.

In sum, macutes were not the ideal unit of Steuart and Montesquieu's imagination. Does that mean that ideal units of account can't exist? I'm hard pressed to come up with a logical explanation for how they might work. And I surely don't have any historical examples, the macute having been confined to the dustbin. I vote we toss the idea out, along with fiat money. Beware economists toting imaginary accounting units, abstract numeraires, and ideal money of account.

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P.S. Indexed units of account like the Chilean Unidad do Fomento, which I wrote about here, are not imaginary units. Instead, I think they should be thought of as ghost monies.

Ghost Money: Chile's Unidad de Fomento

Santiago skyline

This post continues on the topic of the separation of the medium-of-exchange function of money from the unit-of-account function. My previous post discussed how the medieval monetary order was characterized by both a medley of circulating coins and one universal £/s/d unit of account. This post introduces a modern example of medium-unit divergence: the Chilean peso and Chile's Unidad de Fomento. I'll explain how the Chilean system works and end off by asking some questions about the macroeconomic implications of this separation, specifically what happens at the zero lower bound.

Like most modern currencies, the peso is issued by the nation's central bank; the Banco Central de Chile. Local banks offer peso-denominated chequing and savings accounts. Chileans use these pesos as the nation's medium-of-exchange. They pay their bills with pesos, settle rent with it, and buy food with it.

The differences between Chile's monetary system and those of other nations only emerges when we begin look at the unit in which goods are priced. Most nations have one unit-of-account, but Chile has two. While many Chilean prices are expressed in terms of the peso, or P, a broad range of prices are expressed in an entirely different unit, the Unidad de Fomento, or UF. Real estate, rent, mortgages, car loans, long term gov securities, taxes, pension payments, and alimony are all priced using UF. As examples, this real estate website sets prices in UF terms, and this car rental business levies insurance in UFs. On the other hand, wages, consumer good prices, and stock prices are expressed in peso terms.

So what is the UF? The UF was introduced in 1967 by the Chilean government, though it only came into wide use as a unit-of-account in the 1980s. There are no UF coins or notes circulating in the Chilean economy. Rather, the Unidad de Fomento exists as a purely abstract, or indexed, unit-of-account, totally divorced from any media-of-exchange. Goods and services quoted in terms of the UF can only be purchased with an entirely different medium — pesos.

The UF is defined as the amount of currency units, or pesos, necessary for Chileans to buy a representative basket of consumer goods. The amount of pesos in one UF, or the peso-to-UF exchange rate, is calculated daily, and is published on the Banco Central's website. The daily value is interpolated from the previous month's consumer price index, or the Indice de Precios al Consumidor (IPC). If you go to this website, you can see the current peso-to-UF rate and how it has been adjusted over the last week.

This all sounds quite odd, so let's use an example to get a better idea for how the system functions. When a Chilean seller prices something in UF, they are indicating that they expect to receive a fixed quantity of CPI basket-equivalents as payment. For instance, say that a landlord advertises an apartment in downtown Santiago at a monthly rate of 10 UF. A potential renter, curious about the price, checks the UF-to-peso exchange rate at the central bank's website. He sees that today's rate stands at 23,000. Using a cellphone app (in real life, the rate will probably not be a convenient round number), he multiplies 10 UF x 23,000 P/UF to arrive at the current monthly rate in pesos, or 230,000P (this is about US$450). Deciding that the price is good, the renter signs a lease and starts to pay UF-denominated rent each month in pesos.

Say that the Banco Central adopts an easy money policy and six months later the Chilean peso's purchasing power has fallen by around 10%. Rent is still priced at 10 UF. But now the peso content of the UF has risen —after all, it takes about 10% more pesos to buy the same consumer basket. The computed rate on the central bank's website is now 25,000 P/UF. The monthly amount in pesos that the renter must make out to the landlord now comes out to 250,000P (10UF x 25,000 P/UF), up from 23,000. However, while the rent payment is nominally higher, the payment's UF value is constant. In other words, the transaction represents the exact same quantity of CPI baskets as six months before.

It works the same way when the with a tight money policy. Imagine a 10% peso deflation. The UF sticker price stays constant while the conversion rate to pesos on the central bank's website falls by 10%. Rent is nominally lower in peso terms but in terms of representative consumer baskets it has stayed constant.

The UF/P system is similar in many ways to a partially dollarized economy in which the US dollar has been adopted as the unit in which to price long term contracts while the local currency is used to price current goods and services. What makes Chile different from partially dollarized economies is that the dollar tends to circulate along with the local currency as a medium-of-exchange. Thus there are two different units-of-account corresponding to two different media-of-exchange. Chile's UF, on the other hand, is a purely abstract unit with no corresponding medium of its own.

Irving Fisher was skeptical of medium-unit divergence and declared so in his 1913 paper The Compensated Dollar:

Not only would the multiple standard necessitate much laborious calculation in translating from the medium of exchange into the standard of deferred payments, and back again but, if, as has been suggested, the employment of a multiple standard were at first optional, the result would be that many business men whose prosperity depended on a narrow margin between their expenses and receipts would be injured rather than benefited by having one side of their accounts predominantly in the actual dollar and the other in the ideal unit.

Fisher went on to propose his compensated dollar scheme, which was essentially a combined unit-of-account/medium-of-exchange dollar. The real purchasing power of the compensated dollar would stay constant over time, much like the UF/peso combination, but without the necessity of imposing the laborious calculations involved in medium-unit divergence. That Chileans did choose to adopt a somewhat laborious mechanism that involves conversion from/to pesos to/from the ideal UF demonstrates the degree to which they were willing to free themselves of the burdens imposed by the 1970s inflation of the peso. The practice of publishing the UF-to-peso rate on a daily basis—which began in 1977— may have also encouraged UF adoption. Prior to then, the UF had only been calculated monthly.

While the idea of separating the unit from the medium is not a common one, when it does arise it tends to have been inspired by the desire to avoid the deleterious effects of inflation. Widespread use of the UF, as pointed out earlier, came about as a response to 500%+ peso inflation of the 1970s. Robert Shiller, the most vocal modern advocate of unit/medium separation, has also been motivated by concerns over the deleterious effects of inflatio. Shiller believes that because people tend to succumb to money illusion when dealing with inflationary episodes, the adoption of indexed units-of-account may be the most palatable way to reduce the problem.

Just as interesting, however, is the idea of separating the unit-of-account and medium-of-exchange to help cope with deflationary episodes and the zero-lower bound problem

First, let's set up a hypothetical scenario without the UF and a combined peso unit-of-account and medium of exchange. Say the Chilean economy suddenly collapses. Pessimistic Chileans expect to earn a negative return on projects and investments. Peso cash provides a superior return in this environment since it pays 0%—hardly great, but 0% is better than -x%! Peso prices need to fall dramatically in order to restore equilibrium. Put differently, the value of the peso needs to rise to a level at which it is expected to decline at the same rate as all other projects and investments. Yet peso-denominated sticker prices are rigid, preventing the necessary adjustment. What should be a short period of sharp adjustment turns into a long painful period of high unemployment and idle resources.

Now let's assume that all prices are expressed in UF while actual transactions are conducted in pesos. The same shock hits the Chilean economy. Once again the negative yield on projects and investments is overwhelmed by the 0% yield on peso cash. Peso prices need to fall dramatically in order to equilibrate the peso's return with all other yields. As before, sticker prices are rigid.

Here's the difference between our first and second scenarios. In a world with an ideal unit-of-account and no related medium-of-exchange, it really doesn't matter that prices can't adjust. This is because prices are no longer expressed in terms of 0%-yielding peso cash. Rather, they are expressed in terms of UF. Because the UF lacks a physical counterpart, there are no equivalent UF instruments that might also hit the zero-lower bound. The peso's outsized 0% return relative to all other negative yielding assets, which before was the root of the problem, will be quickly equilibrated as the peso-to-UF exchange rate published on the central bank's website jumps higher.

So a shock to an economy in which a combined medium-of-exchange and unit-of-account prevails can quickly become a tragedy. The 0% nature of the former interferes with the stickiness of the latter. But when the medium-of-exchange is divorced from the unit-of-account, the 0% nature of the former will quickly be resolved since stickiness is now in terms of an ideal unit, and not in terms of pesos.

Medium/unit separation, it would seem, could be yet another foolproof way of escaping deflation and the zero-lower bound.

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References:
1. Robert Shiller, Indexed Units of Account: Theory and Assessment of Historical Experience, 1997. [RePEc]
2. Robert Shiller, Designing Indexed Units of Account, 1998. [RePEc]
3. Robert Hall, Controlling the Price Level, 2002. [RePEc]
4. Stephen Davies, National money of account, with a second national money or local monies as means of payment: a way of finessing the zero interest rate bound, 2004

Separating the functions of money—the case of Medieval coinage

Florentine florin

Last year Scott Sumner introduced the econ blogosphere to what he likes to call the medium-of-account function of money, or MOA, defined as the sign in which an economy's sticker prices and debts are expressed. Here and here are recent posts of his on the subject.

I think Scott's posts on this subject have added a lot of depth to the interblog monetary debates. However, I've never been a big fan of Scott's terminology. As I've pointed out before, what Scott calls MOA, most modern economists would call the unit-of-account function of money. Older economists like Jevons and Keynes[1] referred to the unit-of-account as the money-of-account, and modern economic historians also prefer money-of-account. Terminological differences aside, in today's post I want to focus on what I'll call from here on in the unit-of-account function of money.

Scott's UOA posts often emphasize the idea of separating the unit-of-account function from the medium-of-exchange. This isn't a new approach. Back in the 1980s, a trend in monetary economics began whereby economists began to dissociate the various bundled functions of money into constituent components. In fact, a few contributors to the modern econ blogosphere were participants in what was then called "New Monetary Economics", or NME, including Tyler Cowen, Bill Woolsey (pdf), Scott, and Lawrence White (pdf). White, it should be noted, was a critic. Cowen doesn't blog much about NME these days, his last post on the subject was in 2011, but I'm sure every time he goes to a restaurant he can't help but wonder what the world might be like if the menu prices were in different units than the media he expected to pay with. Here is an old Cowen paper (with Krozner) on NME that is worth reading, as well as the bibliography which serves as a good jumping off point to understand more about NME.

But let's turn to an actual example. The separation of the medium-of-exchange from the unit-of-account envisioned by NME isn't mere speculation. Indeed, such a separation has been very much the norm over the last thousand years or so. The medieval monetary system operated with what was essentially a number of heterogeneous media of exchange and an independent unit of account.

Medieval Europe was politically fragmented and many different mints issued coins. Einaudi (pdf) tells us that some 22 gold coins and 29 silver coins (most of them foreign) circulated in the Duchy of Milan alone in the 18th century. This does not include the many varieties of copper coins that would also have been current. Weber (pdf) describes Basel in the 1400s, which had a heterogeneous coinage acquired through trade that included florin and ducats from Italy, and German rhinegulden, along with the local silver penny.

Because most of these coins had different metallic content, and the market value of coins was determined to a large extent by the quantity of metal therein, would this not have caused a terrific amount of confusion? Silver and gold traded at a constantly fluctuating ratios, contributing to the calculational morass. How could shopkeepers and shoppers keep track of the prices at which transactions were to be consummated with such an incredible variety of ever changing units?

The answer is that prices were expressed in terms of a universal unit of account. The name for this unit was the pound, or in French, the livre. The pound (and livre) were further divisible into 20 shillings (sous) and each shilling into 12 pence (deniers). A pound was therefore divisible into 240 pence. Prices and debts were recorded not in terms of individual circulating coins, but in terms of this pound unit of account. Indeed, pound coins never actually existed in Medieval Europe, the pound being a purely abstract accounting unit.

According to Einaudi, local mint officials maintained a list of coin ratings whereby each coin in local circulation was rated at a certain amount of £/s/d. Officials determined the rating by assaying the quantity of gold or silver in each coin. Thus a shopkeeper need only list the price for, say, a horse in terms of the universal unit of account, say 1 pound 6 shillings. A buyer need only look at the 1£ 6s sticker price, determine what sorts of coins he had in his pocket, refer to their public ratings, and compute the proper number of coins to hand over as payment.

Over time, the precious metals content of coins would deteriorate as people 'sweated' coins, filed them, clipped them, or bathed them in aquafortis [2]. The price ratio of gold to silver would often change subject to the whims of market demand as well as mine supply. Sometimes a sovereign might call in an existing issue of coins and reissue them with more or less precious metals therein. When the metallic content of a given coin was changed, or when the market silver-to-gold ratio fluctuated, local mint officials would quickly account for this change by re-rating the altered coin in terms of the £/s/d unit of account.

The advantage to shopkeepers with this system is that they needn't update their sticker prices. After all, via constant re-ratings, the prices of coins were made to fluctuate around the unit of account. For example, if the Spanish doubloon was re-rated due to a debasement in its gold content, our horse-seller could keep his 1 pound 6 shilling price constant, and need simply ask for more doubloons [3]. In this way, the chaos of the medieval coinage system was rendered orderly by a universal £/s/d unit of account.

There is one important issue I haven't dealt with. What defined the medieval pound unit of account? Anyone who's read my old post will know that this question boils down to this—what was the medieval medium of account? The unit of account is always defined in terms of something else, a medium of account, and it is this MOA (which is different from Sumner's MOA) that anchors the price level.

Although city states never minted pounds (and only rarely shillings), they did mint their own pennies. Weber (pdf)(RePEc) and Spufford hypothesize that these pennies served as a foundation, or "link" coin. The penny unit of account was set equal to the penny coin, either spontaneously or via enactment, and thereafter any alteration in the silver quantity of the penny link coin modified the unit of account.

To illustrate, if the sovereign reduced the amount of silver in the local penny, the penny's linkage to the unit of account meant that the penny-as-unit of account now contained a smaller quantity of silver. The pound unit of account (a multiple of 240 pennies) by definition now also contained less silver. So a debasement of the link penny coin meant that all £/s/d sticker prices would need to be raised by shopkeepers if they desired to preserve real purchasing power [4]. In modern days, we call this inflation. Nor was princely debasement of the link coin the sole cause of medieval unit-of-account inflation. After many years of passing from hand to hand, link coin's naturally wore out, and therefore a steady inflation in prices resulted.

A debasement in a foreign penny circulating locally, however, would have no effect on the local unit of account, insofar as the foreign penny didn't serve as the link coin. Rather, a debasement of a foreign penny would result in that particular coin being re-rated in terms of the unit of account. £/s/d sticker prices would stay constant.

In some cases, however, foreign pennies were the link coin, so changes to the silver content of the local penny would have no effect on the price level. Inflation or deflation were imposed exogenously. Even more interesting, in a few rare cases the precious metal content of a famous coin of a previous era that no longer existed was used as the link coin. Monetary historians such as Munro call these "ghost monies". The advantage of having a ghost link coin rather than a current coin is that the unit-of-account could now stay constant over time, preserving the real value of debts and contracts.

To sum up, the medieval unit of account, as we already know, was £/s/d. We also know that there was no single medium of exchange, but a chaotic mix of coin media of exchange. The MOA was a single "index" coin, usually the locally-coined penny, but at other times a foreign coin or an antiquated "ghost coin". While link coins would come and go over the centuries, the £/s/d unit of account stayed constant.

At what point in history did the unit of account and medium of exchange finally fuse together? Weber (pdf) hypothesizes that the Industrial Revolution brought with it improvements in the quality of coin production. Milled edges prevented filing and clipping. The introduction of steam driven coining reduced minting costs and made it more feasible to replace worn coins. These technological improvements meant that it was now possible for coins to serve as stable units of account. The best evidence that Weber finds for this is the appearance of "value marks", or numbers, on the faces of coins. Medieval coins did not carry numbers on them, only the faces and names of the various personages responsible for their issue. The blank nature of these coins allowed the market to determine their exchange rates in terms of the unit of account. The appearance of value marks in the 19th century indicated that the coinage was now of a high enough quality that a separate unit of account was rendered unnecessary. It was now possible to inscribe the unit of account directly on the coin's face.

As a result of these developments, the modern day individual is incapable of imagining a split between the unit-of-account and the media-of-exchange. But this complex institution is something that our ancestors dealt with on a daily basis. Understanding the medieval monetary system is a great way for us to throw off the cobwebs and understand the difference between media-of-exchange and unit-of-account. After all, who knows what future monetary systems might have in store for us — perhaps another divergence between the two functions? It also crystallizes how important the unit-of-account function is. Whoever controls the unit-of-account controls prices, and therefore monetary policy.

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[1] The first line of Keynes's Treatise on Money is: "Money-of-account, namely that in which Debts and Prices and General Purchasing Power are expressed, is the primary concept of a Theory of Money.
[2] Sweating coins involved putting many coins in a sack, shaking the sack, and removing the fine metal grains that shaking had dislodged from the coins. Aquafortis is nitric acid, or HNO3.
[3] The doubloons re-rating due to lower metallic content was called a "crying down" the value of the coin. If the doubloon had been reminted to contain more gold,  its value would have been "cried up". [Editor's Note: this is wrong|
[4] When the link coin's metallic content was debased, this was referred to in the medieval literature as an 'augmentation' or 'enhancement' of prices. When link coin's metallic content was rebased (increased), this was referred to as 'diminution', or 'abatement'. 

Update: By coincidence, Nick Rowe has simultaneously posted on the separation of the functions of money.