Number of union members rose in 2007 (1/30)
In 1983, the first year for which comparable union data are available, the union membership rate was 20.1 percent, according to BLS.
Highlights from the 2007 data include:
• Workers in the public sector had a union membership rate (35.9 percent) nearly five times that of private sector employees (7.5 percent).
• Education, training and library occupations had the highest unionization rate among all occupations, at 37.2 percent, followed closely by protective service occupations at 35.2 percent.
• Among demographic groups, the union membership rate was highest for black men and lowest for Hispanic women.
• Wage and salary workers ages 45 to 54 (15.7 percent) and ages 55 to 64 (16.1 percent) were more likely to be union members than were workers ages 16 to 24 (4.8 percent).
Within the public sector, local government workers had the highest union membership rate, 41.8 percent. This group includes many workers in several heavily unionized occupations, such as teachers, police officers and fire fighters. Private sector industries with high unionization rates include transportation and utilities (22.1 percent), telecommunications (19.7 percent) and construction (13.9 percent).
In 2007, unionization rates were relatively low in agriculture and related industries (1.5 percent) and in financial activities (2.0 percent).
The Service Employees International Union (SEIU), which organizes janitors and security officers, said 114,158 new members joined its ranks in 2007 â€” a 20 percent increase.