What is Money Supply?
Money supply refers to the total stock of money circulating in an economy. It is measured in tiers: M1 includes physical currency and demand deposits (checking accounts), M2 adds savings deposits, money market funds, and small time deposits, and M3 further includes large time deposits and institutional money market funds. In the US, M2 money supply stood at approximately $21 trillion as of early 2025.
Money Supply and Asset Prices
Changes in money supply have significant implications for investors. Rapid money supply growth, as seen during the 2020-2021 pandemic response when US M2 grew by over 25%, tends to boost asset prices in the short term but can fuel inflation with a lag of 12-18 months. Conversely, money supply contraction tightens financial conditions and can pressure equity valuations.
Key Considerations
The relationship between money supply and inflation is not mechanical. Velocity of money (how quickly money changes hands) also matters. During periods of low confidence, increased money supply may sit idle in bank reserves rather than circulating through the economy. Monitoring M2 growth alongside velocity provides a more complete picture of inflationary pressures.