Union membership in Utah manufacturing companies declined from 7.84 percent in 1983 to 5.50 percent in 1987, according to statistics compiled for Grant Thornton's ninth annual Manufacturing Climates Study, scheduled for publication in July.

The drop in union membership in Utah follows a national trend which has seen union membership in manufacturing going from 28.89 percent in 1983 to 25.77 percent in 1987, said Selwin E. Price, a partner in charge of the union statistics project for the national accounting and management consulting firm. The number of union members stood at 4,870,100, compared to 5,005,100 in 1986. "This drop in union membership has taken place in older, highly-organized industries such as steel, metal products and containers, autos, copper and clothing," Price said.In the states surrounding Utah, union membership in Arizona was 4.10 percent; Colorado, 10.68 percent; Idaho, 9.28 percent; New Mexico, 10.82 percent; Nevada, 6.84 percent; and Wyoming, 18.52 percent.