Washington ? We can’t get no job satisfaction.

Even Americans who are lucky enough to have work in this economy are becoming more unhappy with their jobs, according to a new survey that found only 45 percent of Americans are satisfied with their work.

That was the lowest level ever recorded by the Conference Board research group in more than 22 years of studying the issue. In 2008, 49 percent of those surveyed reported satisfaction with their jobs.

The drop in workers’ happiness can be partly blamed on the worst recession since the 1930s, which made it difficult for some people to find challenging and suitable jobs. But worker dissatisfaction has been on the rise for more than two decades.

“It says something troubling about work in America. It is not about the business cycle or one grumpy generation,” says Linda Barrington, managing director of human capital at the Conference Board, who helped write the report, which was released today.

Workers have grown steadily more unhappy for a variety of reasons:

• Fewer workers consider their jobs to be interesting.

• Incomes have not kept up with inflation.

• The soaring cost of health insurance has eaten into workers’ take-home pay.

If the job satisfaction trend is not reversed, economists say, it could stifle innovation and hurt America’s competitiveness and productivity. And it could make unhappy older workers less inclined to take the time to share their knowledge and skills with younger workers.