The Money Supply - M1, M2, and Liquidity
The money supply is the total amount of money circulating in an economy at a given time. Its measurement is more complicated than it sounds because "money" is not a single thing. Cash in a wallet is money. So is a checking account balance. So is a savings account, though it takes a step to convert it to spendable form. A certificate of deposit is money too, but it is locked up for a defined period. The various measures of money supply, labeled M1, M2, and the less commonly tracked M3, capture different layers of liquidity, from immediately spendable cash to broader stores of value.
For investors, the money supply matters because its growth rate has historically correlated with inflation, asset prices, and economic activity. The roughly 40% increase in M2 between February 2020 and April 2022 was the most rapid monetary expansion since World War II, and it was followed by the highest inflation in four decades. Understanding the money supply framework does not make market timing easy, but it provides a macro lens that complements earnings analysis and valuation work.
M1: The Narrowest Measure
M1 represents the most liquid forms of money, the funds that can be spent immediately without conversion or withdrawal penalties. Historically, M1 included physical currency in circulation, demand deposits (checking accounts), traveler's checks, and other checkable deposits.
In May 2020, the Federal Reserve changed the definition of M1 to include savings deposits, which had previously been counted only in M2. This change reflected the elimination of Regulation D's six-transaction limit on savings accounts, which the Fed suspended during the pandemic. The result was a dramatic one-time increase in the M1 figure from roughly $4 trillion to $16 trillion, not because more money was created overnight, but because the definition expanded. This statistical change confounded many money supply analyses and is worth noting when looking at M1 charts that show a vertical spike in 2020.
For investment purposes, M1 is the measure that most directly captures the money available for immediate transactions. When M1 grows rapidly, more cash is available for spending and investment. When M1 contracts, liquidity conditions tighten, and less cash is readily available.
M2: The Workhorse Measure
M2 is the most widely cited money supply measure for macroeconomic and investment analysis. It includes everything in M1 plus savings deposits, money market deposit accounts, small-denomination time deposits (certificates of deposit under $100,000), and retail money market fund shares. M2 captures the money that is either immediately available or easily convertible to spending within a short period.
As of late 2024, U.S. M2 stood at approximately $21 trillion. The growth trajectory tells the story of two decades of monetary evolution. M2 grew at a steady 5-7% annual pace through the 2010s, reflecting normal credit creation and economic growth. Then it accelerated to roughly 25% annual growth in 2020 and 2021 as the combination of fiscal stimulus checks, Fed quantitative easing, and pandemic-era savings drove an unprecedented expansion.
That expansion then reversed. In 2022 and 2023, M2 declined year-over-year for the first time since records began in 1959. The contraction reflected the combined effects of quantitative tightening (the Fed shrinking its balance sheet), consumers spending down their excess pandemic savings, and banks tightening lending standards. This M2 contraction was a headwind for financial markets and coincided with the 2022 bear market in both stocks and bonds.
The relationship between M2 growth and stock market returns is loose but directionally meaningful over medium-term horizons. Periods of rapid M2 growth tend to coincide with rising equity prices because more money in the system bids up asset prices. Periods of M2 contraction or stagnation tend to coincide with flat or falling equity prices. For more context, explore the full economics guide.
M3 and Beyond
M3 adds large time deposits (over $100,000), institutional money market funds, and certain repurchase agreements to M2. The Federal Reserve stopped publishing M3 data in 2006, arguing that it did not provide additional information beyond M2 for monetary policy purposes. Some economists and investors disagreed, noting that M3 captures institutional liquidity that M2 misses.
Several independent research organizations continue to estimate M3, and some investors use these estimates as a broader measure of total liquidity in the economy. The argument for tracking M3 is that institutional money flows, which M2 does not fully capture, drive a significant portion of financial market activity. A large institutional time deposit is not counted in M2 but represents real purchasing power that can be deployed in markets.
Beyond the formal monetary aggregates, liquidity in the modern financial system includes credit from the shadow banking sector, margin lending, securities lending, and derivatives exposures. These forms of "near-money" expand the effective money supply beyond what any single measure captures. When shadow banking liquidity contracts, as it did dramatically during the 2008 financial crisis, the effect on markets can be severe even if M2 remains stable.
The Quantity Theory of Money
The classical framework connecting money supply to prices is the quantity theory of money, expressed as MV = PQ. M is the money supply. V is the velocity of money (how quickly money changes hands). P is the price level. Q is the quantity of goods and services produced (real GDP).
If velocity and output are relatively stable, then changes in the money supply lead proportionally to changes in the price level. This is the basis for Milton Friedman's monetarist assertion that "inflation is always and everywhere a monetary phenomenon."
In practice, velocity is not stable. It has been declining for decades in the United States, meaning each dollar of money supply supports less economic activity than it did in the past. The velocity of M2 dropped from above 2.0 in the late 1990s to approximately 1.2 by 2020. This decline partially explains why the large expansions of the money supply between 2008 and 2019 did not produce significant consumer price inflation: velocity dropped enough to offset much of the money supply increase.
The pandemic period broke this pattern. M2 surged while velocity initially dropped further, but when the economy reopened and consumers began spending their accumulated savings and stimulus payments, velocity recovered. The combination of a dramatically larger money supply and recovering velocity produced the inflationary surge of 2021-2022.
For investors, the quantity theory provides a framework for thinking about the relationship between monetary conditions and future inflation. A sharp increase in money supply does not guarantee immediate inflation, but it creates the potential for inflation when velocity picks up. Monitoring both M2 growth and velocity trends provides a more complete picture than either measure alone.
Money Creation in the Banking System
Most money in the economy is created not by the Federal Reserve directly but by commercial banks through the process of lending. When a bank makes a $500,000 mortgage loan, it does not withdraw that money from a vault. It creates a new deposit in the borrower's account, simultaneously creating both an asset (the loan) and a liability (the deposit). The money supply has increased by $500,000 even though no new physical currency was created.
This process of credit creation is constrained by capital requirements, reserve requirements, and the willingness of banks to lend and borrowers to borrow. When banks are confident about the economy and creditworthiness of borrowers, they lend more aggressively, expanding the money supply through credit creation. When banks become cautious, as they did after the 2008 crisis and again during periodic credit tightening cycles, they pull back on lending, slowing money supply growth.
The Federal Reserve's Senior Loan Officer Opinion Survey (SLOOS) provides quarterly data on bank lending standards and demand. Tightening lending standards are a leading indicator of slower money supply growth and often precede economic slowdowns. When the SLOOS shows a significant share of banks tightening standards, it signals that the credit channel of money creation is contracting.
This is why monetary policy operates with a lag. Even when the Fed cuts rates or expands its balance sheet, the money supply may not grow if banks are unwilling to lend or businesses and consumers are unwilling to borrow. This dynamic played out during the 2010s, when the Fed's massive QE programs expanded bank reserves enormously but actual lending and M2 growth remained moderate because the banking system was still recovering from the financial crisis.
Liquidity Conditions and Market Behavior
For equity investors, the practical application of money supply analysis centers on liquidity conditions. Markets are driven by the intersection of fundamentals and flows. Fundamentals determine what assets are worth. Flows, driven in part by money supply conditions, determine the buying and selling pressure that pushes prices above or below fundamental value.
When liquidity is abundant, investors are willing to pay higher multiples for earnings. More money competing for a finite supply of equities pushes prices up. Speculative assets with no current earnings can attract capital because the opportunity cost of taking risk is low and there is "money to burn." The late 2020 and 2021 period, when M2 was growing at 25%+ and interest rates were near zero, produced the most speculative market environment since the late 1990s.
When liquidity is scarce or contracting, multiples compress. Investors become more discriminating, demanding larger margins of safety and higher earnings yields. Speculative assets are sold first as capital flows toward quality. The 2022 bear market, which coincided with both rate hikes and the beginning of M2 contraction, was characterized by the sharpest repricing of unprofitable growth companies in a generation.
Several proxies for real-time liquidity conditions complement the money supply data, which is released with a lag. The TGA (Treasury General Account) balance at the Fed affects liquidity: when the Treasury builds its cash balance, it drains reserves from the banking system. The reverse repo facility usage indicates excess liquidity parked at the Fed. Bank reserves, published weekly on the Fed's balance sheet, show the raw material that supports lending and market activity.
Monitoring money supply trends is not about precision timing. It is about understanding the monetary backdrop against which all other investment analysis takes place. The same company, with the same earnings and the same growth rate, will trade at different valuations depending on whether the monetary environment is expansionary or contractionary. Incorporating that awareness into portfolio management does not require becoming a monetarist. It requires recognizing that liquidity is the tide that lifts or lowers all boats.
Put these principles into practice. Track fundamentals, build portfolios, and analyze stocks with AI-powered insights.
Start Free on GridOasis →