United States. Bureau of the Census. "Diffusion Indexes," in United States. Bureau of the Census. "April 1982," Business Conditions Digest (April 1982) : 80-83. https://fraser.stlouisfed.org/title/43/item/7428/toc/356804 , accessed on May 13, 2024.
United States. Bureau of the Census. "Diffusion Indexes," in United States. Bureau of the Census. "April 1982," Business Conditions Digest (April 1982) : 80-83. https://fraser.stlouisfed.org/title/43/item/7428/toc/356804 , accessed on May 13, 2024.