Equals total reserves (http://research.stlouisfed.org/fred2/series/TOTRESNSW) less total borrowings from the Federal Reserve (http://research.stlouisfed.org/fred2/series/BORROWW).
Effective February 2, 1984, reserve computation and maintenance periods have been changed from weekly to bi-weekly. Series with data prior to February 2, 1984 have different values reported from one week to the next. After February 2, 1984, the value repeats for 2 consecutive weeks.
Board of Governors of the Federal Reserve System (US), Reserves Of Depository Institutions, Nonborrowed [NONBORRESW], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/NONBORRESW/, July 5, 2015.