United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1978," Business Conditions Digest (May 1978) : 17-18. https://fraser.stlouisfed.org/title/43/item/7381/toc/226173 , accessed on May 7, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1978," Business Conditions Digest (May 1978) : 17-18. https://fraser.stlouisfed.org/title/43/item/7381/toc/226173 , accessed on May 7, 2024.