United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1977," Business Conditions Digest (May 1977) : 65-65. https://fraser.stlouisfed.org/title/43/item/7369/toc/321312 , accessed on April 24, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1977," Business Conditions Digest (May 1977) : 65-65. https://fraser.stlouisfed.org/title/43/item/7369/toc/321312 , accessed on April 24, 2024.