United States. Bureau of the Census. "July 1987," Business Conditions Digest (July 1987). https://fraser.stlouisfed.org/title/43/item/7491, accessed on March 18, 2024.
United States. Bureau of the Census. "July 1987," Business Conditions Digest (July 1987). https://fraser.stlouisfed.org/title/43/item/7491, accessed on March 18, 2024.