Source: U.S. Bureau of Economic Analysis
Release: U.S. International Transactions
This series has been discontinued as a result of the comprehensive restructuring of the international economic accounts (https://apps.bea.gov/scb/pdf/2014/07%20July/0714_annual_international_transactions_accounts.pdf). For a crosswalk of the old and new series in FRED see: http://research.stlouisfed.org/CompRevisionReleaseID49.xlsx.
U.S. Bureau of Economic Analysis, Other Foreign Assets in the U.S., Net: U.S. Treasury Securities (DISCONTINUED) [BOPIPT], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/BOPIPT, February 27, 2020.