United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975). https://fraser.stlouisfed.org/title/43/item/7345, accessed on May 4, 2024.
United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975). https://fraser.stlouisfed.org/title/43/item/7345, accessed on May 4, 2024.