United States. Bureau of Labor Statistics. "September 1990," PPI Detailed Report (September 1990). https://fraser.stlouisfed.org/title/63/item/21661, accessed on April 24, 2024.
United States. Bureau of Labor Statistics. "September 1990," PPI Detailed Report (September 1990). https://fraser.stlouisfed.org/title/63/item/21661, accessed on April 24, 2024.