United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 63-64. https://fraser.stlouisfed.org/title/43/item/7345/toc/405873 , accessed on March 28, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "May 1975," Business Conditions Digest (May 1975) : 63-64. https://fraser.stlouisfed.org/title/43/item/7345/toc/405873 , accessed on March 28, 2024.