What is a Money Stock?

MI - The sum of currency held by the public, plus travelers' checks, plus demand deposits, plus other checkable deposits (i.e., negotiable order of withdrawal [NOW] accounts, and automatic transfer service [ATS] accounts, and credit union share drafts.) M2 - M1 plus savings accounts and small-denomination time deposits, plus shares in money market mutual funds (other than those restricted to institutional investors), plus overnight Eurodollars and repurchase agreements. M3 - M2 plus large-denomination time deposits at all depository institutions, large-denomination term repurchase agreements, and shares in money market mutual funds restricted to institutional investors.