The FRED series Treasury Securities - Assets - Balance Sheet of Households and Nonprofit Organizations is now known as Households and Nonprofit Organizations; Treasury Securities, Including U.S. Savings Bonds; Asset.
The source series id is FL153061505.Q.
This series appears in Table B.101. For further information see the assistance provided in the guide to the Financial Accounts at http://www.federalreserve.gov/apps/fof/.
Board of Governors of the Federal Reserve System (US), Households and Nonprofit Organizations; Treasury Securities, Including U.S. Savings Bonds; Asset, Level [TSABSHNO], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/TSABSHNO, February 25, 2018.