Board of Governors of the Federal Reserve System (U.S.), 1935-. "January 2, 1978," K.11 Holdover Float as Per Cent of Dollar Amounts Received (January 2, 1978). https://fraser.stlouisfed.org/title/3937/item/484589, accessed on November 19, 2018.
Based on the dates of coverage, this is probably the issue for January 2, 1979
Board of Governors of the Federal Reserve System