United States. Bureau of the Census. "January 1981," Business Conditions Digest (January 1981). https://fraser.stlouisfed.org/title/43/item/7413, accessed on March 28, 2024.
United States. Bureau of the Census. "January 1981," Business Conditions Digest (January 1981). https://fraser.stlouisfed.org/title/43/item/7413, accessed on March 28, 2024.