<Table> <Tr> <Td> </Td> <Td> This article relies too much on references to primary sources . Please improve this by adding secondary or tertiary sources . (April 2013) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article relies too much on references to primary sources . Please improve this by adding secondary or tertiary sources . (April 2013) (Learn how and when to remove this template message) </Td> </Tr> <P> In monetary economics, the quantity theory of money (QTM) states that the general price level of goods and services is directly proportional to the amount of money in circulation, or money supply . </P> <P> The theory was challenged by Keynesian economics, but updated and reinvigorated by the monetarist school of economics . While mainstream economists agree that the quantity theory holds true in the long run, there is still disagreement about its applicability in the short run . Critics of the theory argue that money velocity is not stable and, in the short - run, prices are sticky, so the direct relationship between money supply and price level does not hold . </P>

Explain the concept of quantity theory of money
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