United States. Bureau of the Census. "March 1977," Business Conditions Digest (March 1977). https://fraser.stlouisfed.org/title/43/item/7367, accessed on April 19, 2024.
United States. Bureau of the Census. "March 1977," Business Conditions Digest (March 1977). https://fraser.stlouisfed.org/title/43/item/7367, accessed on April 19, 2024.