M2 money supply vs inflation.
The historical relationship.
When M2 grows faster than the productive economy, prices follow with a 12-to-18 month lag. The 2020 stimulus expanded M2 by 24.9% in a single year. CPI peaked at 8.0% in 2022. The chart below plots both series since 2000 so you can see when money-supply spikes lead inflation spikes and when they do not.
This is an educational visualization, not a calculator. Toggle the lag marker to see the 2020 to 2022 relationship explicitly. Pull live numbers from FRED before referencing the exact figures.
If velocity (V) and real output (Q) are roughly stable, then money supply growth (M) determines price growth (P). Doubling M with stable V and Q roughly doubles prices. The complication: V is not stable. The 2008-2015 QE expansion did not produce the inflation many predicted because velocity collapsed simultaneously. The 2020-2022 expansion did, because velocity recovered while M2 was already much larger.
M2 grew 24.9% in 2020, the largest single-year expansion in modern US history. CPI followed 12 to 18 months later, peaking at 8.0% in 2022. M2 growth then turned negative in 2022 to 2023 as the Fed tightened. CPI moderated through 2023 to 2024, consistent with the monetarist lag model verify×DON'T TRUST, VERIFYClaim: US M2 grew approximately 24.9% in 2020 and CPI peaked at 8.0% in 2022.Verify at: FRED M2SL ↗ · FRED CPIAUCSL ↗Year-over-year December figures from FRED. Earlier annual values are interpolated approximations; verify the exact prints before citing in print..
Money supply growth predicts inflation with a lag and with noise. The 2008 to 2015 QE expansion did not produce proportional consumer-price inflation because velocity of M2 collapsed simultaneously. The relationship between M2 and CPI is real but not mechanical. Velocity, productive capacity, and supply shocks all matter. Treat the chart as a strong signal, not a forecast.
Sources and methodology
- M2 series: FRED M2SL. Year-over-year percentage change in seasonally-adjusted M2 stock at year-end.
- CPI series: FRED CPIAUCSL. Year-over-year percentage change in CPI for All Urban Consumers, all items, December over December.
- The Fed redefined M1 in May 2020 (savings deposits added). M2 was less affected by the redefinition; the series remains comparable across the boundary.
- The 12-to-18 month lag is a rough rule from monetarist literature, not an exact mechanism. Friedman wrote of long and variable lags; the actual delay in any given cycle depends on velocity, expectations, and supply conditions.
- This tool uses hardcoded annual approximations to keep the page fast and offline-friendly. For minute-by-minute live data, go to FRED directly.
What this changes for your money
- Watching M2 growth gives an early read on inflation 12 to 18 months out, before it shows up in your grocery bill or rent.
- When M2 accelerates significantly above GDP growth, cash holdings begin losing real value before the official CPI prints catch up. The protection (TIPS, equities, real assets, sound-money assets) needs to be in place ahead of the lag.
- When M2 contracts (as in 2022 to 2023), the lag works the other direction: inflation moderates 12 to 18 months later. Don't anchor portfolio decisions to the inflation print at the time you see it; look at the M2 trend.
Related
Not financial advice. Educational visualization; verify exact figures against FRED.