The FRED series Total Credit Market Assets Held by Domestic Financial Sectors - Commercial Banking (Discontinued Series) is now known as U.S.-Chartered Depository Institutions; Credit Market Instruments; Asset.
The source series id is FL764004005.Q.
This series still appears in Table L.1. The series will continue to update. However, the Board of Governors will no longer feature this series in the Z.1 Flow of Funds release. For further assistance see the information provided in the guide to the Financial Accounts at http://www.federalreserve.gov/apps/fof/.