U.S. unemployment rate nudged down in April with job growth continue to decelerate and labor force shrank, a fresh sign of a mixed picture of U.S. economic recovery.

The Labor Department figures showed that jobless rate fell to 8. 1 percent last month, the lowest level since January 2009. It has fallen a full percentage point since last August.

The decline in the unemployment rate was not due to job growth, but that more people dropped out of the labor force.

Employers pulled back on hiring for the second straight month. Total nonfarm payrolls rose by 115,000 jobs in April, less than the revised 154,000 job gain in March and the average level of 252, 000 registered from December to February.

The private sector added 130,000 jobs while governments of all levels slashed 15,000 posts. Employment rose in manufacturing sector by 16,000 while private service-providing sector added 116, 000 jobs during the month, the Labor Department said.

Moreover, the labor force participation rate, the share of adults working or looking for work, has declined to 63.6 percent, the lowest level in more than 30 years. More than 300,000 people gave up looking for jobs and no longer counted as unemployed.

"Despite adverse shocks that have created headwinds for economic growth the economy has added private sector jobs for 26 straight months, for a total of 4.25 million payroll jobs over that period," Alan Krueger, chairman of the White House Council of Economic Advisers, said on Friday.

He noted although labor force participation fell over the month, nearly three-quarters of the 1 percentage point drop of jobless rate since August is attributable to increased employment.

The number of unemployed Americans was little changed at 12.5 million. And the number of long-term unemployed, people who have been jobless for more than 6 months, stood at 5.1 million, accounting for 41.3 percent of the total unemployed.

Average hourly earnings for all employees rose by 1 cent to 23. 38 U.S. dollars. It has increased 1.8 percent over the past year.

The decelerated payroll increase was a reminder of the bumpy economic recovery. The overall economy grew by 2.2 percent annual rate in the January-March quarter, down from 3 percent growth in the fourth quarter last year.

Despite less-than-expected job growth, there are helpful signs for continuous improvement of U.S. labor market. Payroll increases for February and March were revised upward by a combined 53,000. And a separate report on Thursday showed that the number of people initially applying for jobless benefits dropped to 365,000 last week, below the 375,000 threshold to indicate a sustained drop in the unemployment rate.

Federal Reserve officials said in an April 25 statement that labor market conditions had improved in recent months and that the unemployment rate declined but remained elevated.

They forecast that the unemployment rate would fall to 7.8 percent to 8 percent by the end of the year, which bodes well for the reelection of the incumbent president Barack Obama.