Union membership as a percentage of the Illinois work force increased in 2009, even as the figure dropped slightly nationwide, the U.S. Bureau of Labor Statistics said in a report released today.

The 941,000 union members in the state represented 17.5 percent of the work force last year, up from 16.6 percent in 2008. At its peak in 1993, union members accounted for 21 percent of the Illinois work force.

Nationwide, union membership fell 771,000 to 15.3 million, or 12.3 percent of the work force compared to 12.4 percent in 2008.

The bureau report found Illinois has had union membership above the national average since 1989.