Source: Board of Governors of the Federal Reserve System (US)  

Release: H.4.1 Factors Affecting Reserve Balances  

Units:  Millions of U.S. Dollars, Not Seasonally Adjusted

Frequency:  Weekly, As of Wednesday

Loans is the sum of "Primary credit," "Secondary credit," "Seasonal credit," "Term Asset-Backed Securities Loan Facility," and "Other credit extensions.