The Adjusted Monetary Base is the sum of currency (including coin) in circulation outside Federal Reserve Banks and the U.S. Treasury, plus deposits held by depository institutions at Federal Reserve Banks. These data are adjusted for the effects of changes in statutory reserve requirements on the quantity of base money held by depositories.
This series has been reconstructed starting July 14, 2003. For further information, please go here for the article and here for historical data and components.
Federal Reserve Bank of St. Louis, St. Louis Adjusted Monetary Base [BASE], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/BASE, September 19, 2019.