The association's index declined in August for the fourth straight month, to the lowest level since 1982.
Prices declined for the ninth consecutive month and at the greatest rate since December 1982.
Government jobs declined for the third month as census workers were laid off.
The report said, however, that the rate of price increases declined for the sixth consecutive month.
Construction spending in March declined for the third consecutive month.
The manufacturing sector declined for the sixth consecutive month, but at a lesser rate.
Despite growth in production and new orders, for example, employment declined for the third consecutive month.
Also, prices declined for the seventh consecutive month, at a slightly higher rate than in November.
Prices declined for the seventh straight month, at a somewhat faster pace than in November, the report said.
Business activity declined for the third straight month in November.