United States. Bureau of the Census. "Diffusion Indexes," in United States. Bureau of the Census. "June 1985," Business Conditions Digest (June 1985) : 79-81. https://fraser.stlouisfed.org/title/43/item/7466/toc/375565 , accessed on March 28, 2024.
United States. Bureau of the Census. "Diffusion Indexes," in United States. Bureau of the Census. "June 1985," Business Conditions Digest (June 1985) : 79-81. https://fraser.stlouisfed.org/title/43/item/7466/toc/375565 , accessed on March 28, 2024.