These comments are for the career grouping of Plumbers, Pipefitters and Gas Fitters.
People in this group work for maintenance departments of factories, plants, and similar organizations; trade contractors; and gas utility/servicing companies. They may also be self-employed.
The unionization rate (56%) is above the average (32%) for all occupations.
Here are the average annual salaries.
2010: $52,354
2005: $43,077
2000: $36,496
1995: $35,772