M2 money supply

M2 adds together the narrowest form of money, physical cash and checking deposits (M1), plus savings accounts, small time deposits, and retail money market funds. It's a stock measure, a snapshot of total money outstanding at a point in time, reported monthly by the Federal Reserve, and it's usually read as a year-over-year growth rate rather than the raw dollar figure, since the raw level only ever grows over a long enough horizon.

The growth rate matters more than the level. Rapid M2 expansion is generally read as more liquidity available to chase spending and asset prices, while a contraction, negative year-over-year growth, is comparatively rare historically and has coincided with tighter financial conditions and, at times, stress in equity markets. The 2022-2023 period saw the first sustained M2 contraction in decades, which some analysts flagged as a headwind for risk assets even as other indicators looked resilient.

The relationship between M2 growth and inflation, once treated as a near-mechanical link in monetarist economics, has been unreliable in practice for decades. The sharp M2 expansion during 2020 and 2021 was followed by a genuine inflation surge, but M2 growth has also run hot in other periods with no comparable inflation response, largely because how fast that money actually turns over and gets spent, its velocity, varies enormously and isn't captured by the M2 figure itself. Treat M2 as one liquidity gauge among several, not a standalone inflation forecast, and never assume a fixed lag or magnitude between an M2 move and a specific CPI or PCE outcome.

Suppose M2 is running at 3.8% year-over-year growth, roughly back near its pre-2020 historical average after the sharp swings of the pandemic years. That's a return to a liquidity backdrop closer to normal, without the tailwind of the 2021 expansion or the headwind of the 2023 contraction. Compare that to a hypothetical reading of minus 2%, an outright contraction, which would suggest tightening financial conditions worth watching alongside credit spreads and bank lending surveys, even though no single M2 reading translates into a precise forecast for stocks or inflation on its own. Either reading is best paired with what credit markets and bank lending standards are doing at the same time, rather than read as a standalone signal.