Half of the U.S. population currently participates in the nation's labor force. Among 148 million wage and salary workers, 79.2 million are men and 68.7 million are women, representing sixty-six percent of the civilian noninstitutional population over 16 years old. The average worker in 2003 earned an annual wage of $36,210. Earnings averaged $17.18 per hour for all workers (in private industry and State and local government), with White-collar* occupations averaging $21.09 per hour, and Blue-collar* occupations averaging 14.51 per hour. Labor union members account for 13 percent of wage and salary workers nationwide**, with membership varying greatly by state, from 25 percent in New York to just 3 percent in North Carolina. Over 7 million workers hold down at least two jobs, and in well over half of these cases one of the jobs held is full-time. Ten percent of workers have worked for their current employer more than 20 years, while the median duration on the job is 3.7 years. Seventy-seven percent of workers drive alone to work and spend an average of 24.4 minutes getting there.