WASHINGTON -- Clean-energy jobs make up a small part of U.S. employment, but a new federal report shows they are growing much faster than other work, even healthcare.

The nation had about 3.4 million green energy jobs in 2011, the Bureau of Labor Statistics said Tuesday in its second annual and final look at this emerging category of employment. (More on why it's the last report later.)

In all, so-called green jobs accounted for just 2.6% of all employment that year, but a comparison with 2010 data shows that these jobs grew at four times the rate of all the others combined. Green employment jumped 4.9% in 2011 from the prior year. That compares with a gain of 1.2% for all jobs and 2.7% for restaurants, 1.7% for manufacturing and 1.8% for healthcare, which is often seen as the fastest-growing sector.

Green jobs of course cut across industries. By the BLS definition, they include work that is primarily involved in the production of green goods and services -- for instance, renewable energy, pollution reduction and recycling, and natural resources conservation. The agency also counts as green those jobs that involve education and training related to environmental compliance.