United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "July 1988," Business Conditions Digest (July 1988) : 18-19. https://fraser.stlouisfed.org/title/43/item/7503/toc/420485 , accessed on March 29, 2024.
United States. Bureau of the Census. "Composite Indexes," in United States. Bureau of the Census. "July 1988," Business Conditions Digest (July 1988) : 18-19. https://fraser.stlouisfed.org/title/43/item/7503/toc/420485 , accessed on March 29, 2024.