Spotykam się czasami ze wzorem M * V = P * T
(M - supply of money, V - velocity of circulation, P - general price level and T - volume of trade)
Ale jakoś to do mnie nie przemawia. W artykule poniższym gość podważa tę teorię, ale nadal nie jest to dla mnie jasne.
Czy jest coś takiego jak szybkość obrotu pieniądza w gospodarce czy go nie ma ?
Hazlitt wrote that in 1968 in an essay in which he demolished the velocity of money notion.
Simply put, the idea "refers to the rate at which money circulates, changes hands or turns over." It is a very old idea, harking back to the days when the "mechanistic quantity theory" of money predominated. That is, before we understood how individual judgments determined value, this concept of velocity explained variations in the value of money that were out of proportion with the variations in its supply. Under the mechanistic quantity theory, such changes were to be proportional.
Fisher adopted the idea of velocity in his dubious formulation MV=PT (where M is the supply of money, V is its velocity of circulation, P is the general price level and T is the volume of trade).
Both the mechanistic quantity theory and Fisher's equation have long since been refuted. No credible economist takes either of them seriously. But the idea of the velocity of money has survived, nevertheless, and today it's a pain in the neck. Hazlitt's insights were as follows.
First, as far as Fisher's equation goes, velocity (V) is not an independent variable. It is always exactly equal to the volume of trade T, and is driven by trade, not vice versa - it does not drive trade:
"What we have to deal with, in the so-called circulation of money, is the exchange of money against goods. Therefore, V and T cannot be separated. Insofar as there is a causal relation, it is the volume of trade which determines the velocity of circulation of money, rather than the other way around… the velocity of circulation of money is, so to speak, merely the velocity of circulation of goods and services looked at from the other side. If the volume of trade increases, the velocity of circulation of money, other things being equal, must increase, and vice versa."
Changes in the velocity of circulation are thus the effect, and not the cause, of changes in the demand for money and/or goods. The concept is a makeshift explanation for the factors affecting the demand for money. For example, if the price level did not change in direct proportion to the money supply, the "Fisherine quantity theorists" would explain it with reference to changes in the velocity of circulation.