Wednesday, 8 February 2012

Meaningless statistics: The Velocity Of Money

1. AC1 reminded me about this 'velocity of money' nonsense, which he, along with a lot of other people seem to believe in, so I might as well tick that one off my 'blogging to do list.

2. The accepted method of calculating the velocity of money appears to be dividing annual GDP by the amount of money in circulation, and you can make up your own mind which measure of money supply you want to use.

3. It is quite clear that we can measure GDP in a barter economy as the sum total of the value all goods and services produced or provided. Using one currency to express the value makes the figures much more manageable. If last year output was 1,000 sheep and 5,000 tonnes of wheat and this year output is 2,000 sheep and 4,000 tonnes of wheat, has the value of output gone up or down? We can only say for sure if we know the prices, i.e. relative values, of sheep and wheat.

4. Whether you include the value of own-consumption is a fundamental flaw in measuring real GDP, which "falls when a man marries his housekeeper" as the old saying goes, and applies as much whether it's a barter economy or whether most exchanges are goods/services for cash. There are plenty of other made up figures or missing figures, so GDP in absolute terms is no more than a rough guide, although changes from year to year and comparisons between countries are relevant.

5. Then we have a bewildering array of measures of money supply, which go from M0 (coins and notes in circulation, easy to understand but basically meaningless as most transactions are between bank accounts) up to MZM. While relative changes from year to year in any of these measures might be mildly interesting, in isolation they are all meaningless as well. If everybody took the cash from under the mattress and paid it into the bank, then M0 would fall, but MB stays the same.

Not only that, the whole concept of "supply" is misleading anyway, as you could just as well look at total debts. Remember that total financial liabilities always equal total financial assets, and the two net off to precisely zero. So if a politician says "money supply increasing" that sounds like A Good Thing (unless you worried about inflation) but if he says "debt is increasing" that sounds like A Bad Thing. In fact they are two sides of exactly the same thing. Remember also: the assets could be fictitious but the debts are real.

6. Logic says that GDP is a fairly stable figure and that most people live from month to month, so in a pure cash economy (i.e. using M0 as the measure), we'd only need enough coins and notes to cover one month's income/expenditure and velocity would be twelve. If some people hoard cash under the mattress, then the government has to print some more, so velocity goes down a bit, but cash under the mattress is not part of GDP. If everybody has enough cash under the mattress to cover themselves for one month's expenditure, then velocity goes down from twelve to six. This is neither A Good Thing nor A Bad Thing.

7. Yes, the reader shouts, but what if everybody decides that the good times will never end, takes that cash from under the mattress and goes on an almighty spending spree? Well, some people might respond by opening their shop for longer hours, and factories might increase their output and so on, but this boost to GDP would be very short lived (and would suck in imports and lead to short lived inflation), this level of spending is only sustainable if everybody also works double the hours and so on, so the chances are, a month later, all that cash would be back under the mattress (minus what was spent abroad on imports).

8. By this stage, the cunning reader might have noticed that if the top part of the fraction (GDP) is fairly fixed and the bottom part (the money supply) is a made up number. The resulting 'velocity' is merely the inverse of a made up number.

9. Quite correct. From an article at Seeking Alpha headed "Money velocity continues to plunge":

The US Federal Reserve is engaged in an historic liquidity operation intended to support economic recovery. Since the recession in 2008, M1 money supply has surged an astonishing 60 percent [from $1.4 trillion to] the $2.2 trillion level in January, with no end in sight to the extreme move higher. However, during that time, the velocity of M1 money has plunged from a high of 10.37 in late 2007 to 7.09 in late 2011.

Here are his supposedly terrifying charts:10. Well, duh.

Working backwards, at the start of the three-year period, nominal GDP was $14,500 trillion (10.37 x $1.4 trillion) and at the end it was $15,600 trillion (7.09 x $2.2 trillion), knock off 2.5% a year for inflation and we come to the amazing conclusion that, er, US GDP flat lined over the three years, which we knew already, having already worked out GDP in order to be able to calculate money velocity in the first place.

It just so happens that the US government had done all the Quantitative Easing over there to keep their mates the bankers afloat, but that extra $0.8 trillion just stayed in the bank, it was just numbers on bits of paper with no impact on the real world.

11. Here endeth.

27 comments:

Barnacle Bill said...

Well that's me confused then!

I thought the velocity of money was how quickly them above us proles managed to get it from our pockets to theirs'.

Mark Wadsworth said...

BB, unlike official money velocity, that would be a very interesting and relevant statistic, you should copyright it and start publishing it every month :-)

Fraggle said...

I've never been able to quite shake from my head the idea that GDP and money velocity are actually entirely synonymous. But then, I don't really understand the idea that velocity is important in anyway. It seems entirely dependant on how we structure our lives and is just a by-product. Surely if we budgeted weekly rather than monthly, velocity would be 52 and no-one would be any the wiser?

In any case, you always have to be suspicious of any formula with unitless variables in it.

Richard said...

Money velocity is an identity so you you can't believe in it or disbelieve, it exists.

Probably the best way to think about it is that velocity=nominal income divided by the money supply.

Every pound spent or turned-over is a pound of income for someone else.

Velocity drops and income drops.

Income drops and output drops and unemployment rises.

Therefore, velocity in the economy is a measure of income-adjusted money demanded. When velocity is higher, the income-adjusted demand for money is lower. If velocity plummets, this means that income-adjusted money demand has spiked and the output of the economy will correspondingly fall.

By definition MV=PY. Money and its velocity equals output and the price level. However, velocity is not constant and is endogenous as the monetarists discovered when they tried to target monetary aggregates in the early 1980s.
http://marketmonetarist.com/2011/10/31/the-inverse-relationship-between-central-banks-credibility-and-credibility-of-monetarism/


There may be 'a bewildering array of measures of money supply ', but they all have a velocity. The only monetary aggregate that a body like the BoE would pay much attention to is M4ex.

Mark Wadsworth said...

F, yes, in a cash-only society, if we were all paid weekly and paid our rent and mortgages weekly, then we'd need much less coins and notes and money velocity would be 52.14.

R: "Probably the best way to think about it is that velocity=nominal income divided by the money supply."

Yes, that's how it is defined or measure, that's what I said. Nominal income is the only on which is very important, the other two aren't. That doesn't make velocity "real". I could just as well divide our GDP by the age of our monarch, because GDP is real and the queen has a known age. But GDP divided by age is meaningless.

"Velocity drops and income drops. Income drops and output drops and unemployment rises."

Well no.

Velocity might drop because there has been an increase in money supply. And velocity drops because income drops, in the same way was income drops because velocity drops.

Similarly, income drops because output and employment drop, they are all part of the same thing.

And so on.

Anonymous said...

Money Velocity is a rough measure of Comparative Advantage. How we exchange our time with others, and thus raise productivity. It's exactly analogous to the looping of debt/credit pairs through the banking system.

AC1

Ralph Musgrave said...

I agree that the velocity of circulation of money is not the most crucial of all economics variables. But it’s an idea that anyone trying to understand economics should be aware of. Coincidentally I was talking to two chemistry graduates who were interested in the credit crunch last night, and they didn’t understand why GDP was not directly related to the money supply. I just explained that the velocity of circulation can vary. Plus I quoted the fact that the velocity in New York state in 1932 was a third of what it had been in 1929. And they immediately got it.

Mark Wadsworth said...

AC1: "Money Velocity is a rough measure of Comparative Advantage"

No it's not. There are far better ways of measuring comparative advantage.

RM: "the velocity in New York state in 1932 was a third of what it had been in 1929"

Yes, but that might mean same money supply, GDP fallen by two-thirds; it might mean money supply trebled and GDP same (which is what Seeking Alpha overlook).

Lola said...

I have also velocity of money used to 'explain' 'inflation'. Which personally I think is nonsense. I mean you can have a lot more velocity of money in say London, than say, Penrith, yet prices (w.e.o property) of most goods and services are not chnaging any quicker.

Mark Wadsworth said...

L, agreed, using a made up figure to explain two separate effects "monetary inflation" and "government made inflation" (using your definitions) is totally daft.

Lola said...

MW 'Totally daft' just about sums up most of the 'economic policy' made by all shades of politicos...but they and their attendent bureaucracies just love these high-fallutin' sounding cod-economic theories that they can latch onto and try to use to bamboozle the Poor Sod on the Clapham Omnibus, gawd help us.

Dinero said...

How about comparing a graph of velocity of money with a graph of price inflation both normalised for GDP.

Bayard said...

The phrase "velocity of money" makes me think of those pneumatic tube systems you used to get in department stores, where the cashiers would put the banknotes in a plastic bullet-thing, shove it into a tube and it would go shooting off to God knows where. That was real money with real velocity.

Deniro said...

And normalized for money supply.


Alternatively constant velocity and change in money supply.

Lola said...

Deniro - 'constant velocity' - now there's something really interesting when associated with power transmission. The invention of CV joints to solve the problems inherent in the geometry of UJ's (Hooke's Joints) is really interesting and important, and solves a genuine problem, unlike velocity of money, which is bollocks imho.

Derek said...

If you really want to see how meaningless the MV=PY equation is, try doing dimensional analysis on it.

Units of the variables
M is measured in $
V is measured in $*Transactions/Time
P is measured in $/TransactableItem
Y is measured in TransactableItems/Time

which implies that the left-hand side of the equation has dimensions of $ squared per unit-of-time whereas the right-hand side has dimensions of $ per unit-of-time. So the two sides of the equation are calculating two different kinds of things.

Scientists generally take that as proof that the equation needs modification. In this case I would say that V needs to be changed to be frequency of transactions rather than velocity of money.

Now I realise that there's room for argument about the units that should be assigned to each of the variables, so if anyone has different thoughts on that let's hear them but the general principle that the equation is only valid if the units of the left-hand side are the same as the units of the right-hand side is still true.

And assuming that I've got the units correct that means that the equation is invalid.

Mark Wadsworth said...

L, yes, it is nonsense.

Den, that sort of thing is Steve Keen's territory, not mine. I like simple things.

B, it reminds me of watching the bathwater spiral down the plug hole and disapper.

D, are you sure?

GDP = $/year
Money supply = $
Velocity = {$/year)/$
The $'s cancel out top and bottom, and the resulting units are "per year".

So in that sense it is quite accurate. If there are no bank accounts, GDP is $1,200 per year and all transactions done in cash and everybody lives month to month, we clearly only need $100 in circulation.

Then
GDP = $1,200/year
Money supply = $100
Velocity = 12/year.

In the same way that 1 Hertz = 1 per second, this just happens to be "per year". It's a perfectly valid unit, it's just that the number itself is meaningless.

Or more to the point, all SeekingAlpha's charts prove is that "printing more money and parking it in the bank does not help the economy" which we knew anyway.

Dinero said...

If the GDP is £100 and there is only one single £5 note in circulation then it must of changed hands twenty times. So V=20.

Dinero said...

I agree with your "parking it at the bank" concept. In some limited respects money only exists during a transaction

Mark Wadsworth said...

Din, V = 20/year, correct.

"In some limited respects money only exists during a transaction"

That's quite a good way of looking at things.

In some respects, cash under the mattress (or ones and zeroes on an computer) is just waste paper (or a waste of electricity). If the house burns down and the paper money destroyed, what impact does that have on national wealth? Precisely none. And if there were a power cut at the Bank of England and all the ones and zeroes disappeared, would the average person are or even notice? Methinks not.

Bayard said...

"And if there were a power cut at the Bank of England and all the ones and zeroes disappeared, would the average person are or even notice? Methinks not."

But if someone let off one of those bombs that destroys everything electronic but nothing else and the bank sent you a letter saying we have no record of your mortgage/savings, I think the average person would care quite a bit.

DBC Reed said...

The problem with dispensing with the concept of the velocity of money is that it hamstrings a lot of pro Land tax argument.
Such as: postwar economy relies on Keynesian velocity stimulus;people spend money because there is built- in inflation and there is no point in hanging on to it. Result:"You've never had it so good".Tory bumheads then get rid of Schedule A taxation on house price rises in 1963 and the system suffers a dramatic loss of pressure as the circulating money starts leaking into land/property.
(There is n't the time to go into how Keynes watered down the original proposals by Silvio Gesell for Stamp Money which you would have to pass on before the next stamp (ie. a tax) would come due at the end of the week or Gesell's complete understanding of the role played by land which Keynes flunked: he never did any recogniseable course in Economics).

I would think you could negotiate your way round the problems without using V of M but only like Edddie Carlton who played off three cushions to get the cue ball behind where it started while everybody else would just screw it back up the table.
I would have though the present situation where homeowners have been gifted hundreds of pounds a month in reductions to variable -rate mortgages (by Darling originally) but won't spend any money in the shops is a pretty clear indication of low velocity of money.
Lets hear it for Bible Bill Aberhart!

Mark Wadsworth said...

B, I would be absolutely bloody livid, but it wouldn't mean that I stop going out to work or anything.

DBC: "homeowners have been gifted hundreds of pounds a month in reductions to variable -rate mortgages (by Darling originally) but won't spend any money in the shops"

Yes. But simply imposing LVT and cutting other taxes reverses the transfer of wealth from homeowners to productive economy, it's no more complicated than that.

Forget about all this 'stamping' or 'velocity' nonsense, it is quite simple, when a government spends, it creates money out of thin air. And when it taxes, it destroys it again (to prevent inflation, if nothing else).

So the government can spend what it wants and then to prevent the worst kind of inflation, land prices, it can tax land values, all sorted.

DBC Reed said...

I don't see that there's any disagreement:you say LVT will get cheap money back into cirulation: I say this is increasing the velocity of money.There's not a lot of difference in effect.
The only sticking- point would be if you disagreed that Keynesian remedies work by stopping people hanging onto money with consequences for velocity.
It is no use "forgetting" the velocity of money :it does exist and will not go away.
Neither does it help to say that governemnts pay for things by creating money out of thin air( Ithought you believed that QE does n't exist either?).Governments get money by taxation, that makes people pay for the services they receive: governments also borrow via bonds.
The honest and clear thing would be for governments to pay for infrastructure and sewrvices by the unsupported cheques of QE and to have |LVT to mop up any leaks into the land market.

Mark Wadsworth said...

DBC: "Neither does it help to say that governemnts pay for things by creating money out of thin air (I thought you believed that QE doesn't exist either?). Governments get money by taxation, that makes people pay for the services they receive: governments also borrow via bonds."

a. Governments can create money out of thin air, it's called running a deficit. Clearly, if they do this long enough, more than a couple of years, it all gets very unpleasant, you either get hyperinflation or currency collapse (see: Zimbabwe).

b. I never said QE didn't exist. I said that all it amounts to is the government borrowing short (overnight) instead of borrowing long (5 or 10 year bonds).

c. Governments get (and destroy) money by taxation, agreed. But remember how it works with banks, they can make a loan out of thin air and it comes back as a deposit. It's the same with governments, it's perfectly valid to say that they spend first (print money) and then tax later (destroy money).

So yes, we are agreed on the actual desired course of action, we merely appear to disagree wildly on what fancy names we apply to each individual step in the DBCReed-onomic system.

jdk said...

have you ever plotted M1 and Tax receipts?

Mark Wadsworth said...

JDK, no. Have you? What relevance does it have comparing a fairly meaingless figure with a fairly important one?