United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "August 1981," Business Conditions Digest (August 1981) : 66-66. https://fraser.stlouisfed.org/title/43/item/7420/toc/89342 , accessed on May 10, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "August 1981," Business Conditions Digest (August 1981) : 66-66. https://fraser.stlouisfed.org/title/43/item/7420/toc/89342 , accessed on May 10, 2024.