Source: U.S. Bureau of Economic Analysis
Release: U.S. International Transactions
Note that the 1962 Q1 value of 0.000 represents less than +- $500,000.
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, Foreign Official Assets in the U.S.: Net (DISCONTINUED) [BOPIO], retrieved from FRED, Federal Reserve Bank of St. Louis; https://fred.stlouisfed.org/series/BOPIO, December 14, 2019.