http://blogs.wsj.com/economics/2011/05/06/why-did-the-unemployment-rate-rise-2/The economy added 244,000 jobs in April but the unemployment rate skipped from 8.8% to 9%. What gives?
The number of jobs added comes from a survey of establishment payrolls. The unemployment rate comes from a separate survey of U.S. households. The household survey is much smaller than the establishment survey, and as a result it can swing around a lot — and move the unemployment rate up and down when it does. That volatility is a big reason why economists usually, but not always, pay much more attention to the establishment report.
In April, the household survey registered a loss of 190,000 jobs, while the labor force — the number of people working or looking for work, stayed about the same. And so the unemployment rate went up.
The household survey also includes workers that don’t show up in the establishment survey, like farmers, the self-employed and people who work without pay in the family store. In April, that difference apparently accounted for a lot. Adjusting the figures to make an apples-to-apples comparison with the establishment survey, the household survey showed a gain 50,000 jobs, according to the Labor Department.