The most common measures are named M0 (narrowest), M1, M2, and M3. In the United States they are defined by the Federal Reserve as follows:
|M0||The total of all physical currency, plus accounts at the central bank that can be exchanged for physical currency.|
|M1||M0 + those portions of M0 held as reserves or vault cash + the amount in demand accounts ("checking" or "current" accounts).|
|M2||M1 + most savings accounts, money market accounts, and small denomination time deposits (certificates of deposit of under $100,000).|
|M3||M2 + all other CDs, deposits of eurodollars and repurchase agreements.|
The Federal Reserve stopped publishing M3 statistics in March 2006, saying that the data cost a lot to collect but did not provide significantly useful information 1. The other three money supply measures continue to be provided in detail.