United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "March 1980," Business Conditions Digest (March 1980) : 66-66. https://fraser.stlouisfed.org/title/43/item/7402/toc/213866 , accessed on May 7, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "March 1980," Business Conditions Digest (March 1980) : 66-66. https://fraser.stlouisfed.org/title/43/item/7402/toc/213866 , accessed on May 7, 2024.