U.S. non-farm payrolls, a key measure of the economy's health, rose in March for only the third time since recession struck in late 2007 as the private sector stepped up hiring at the fastest pace in almost 3 years.

Employers added 162,000 jobs last month, the Labor Department said on Friday, leaving the unemployment rate steady at 9.7 percent for the third straight month. The payrolls increase was the largest since March 2007, and also reflected temporary hiring for the census.

Payroll figures for January were revised to show a 14,000 gain, while February was adjusted to show only a loss of 14,000.

Analysts polled by Reuters had expected non-farm payrolls to rise 190,000 last month and the unemployment rate to hold steady at 9.7 percent. The median projection from the 20 economists who have forecast payrolls most accurately over the past year predicted 200,000 jobs were created in March.

The labor market has lagged the economy's recovery from the worst downturn since the 1930s, creating a political challenge for President Barack Obama.

Job growth is critical to keeping alive the recovery, which started in the second half of 2009, once government stimulus efforts and a boost from businesses' rebuilding inventories fade.

Employment growth is the last piece of the puzzle. We need job growth and labor income growth in order to have a sustainable economic recovery, said Zach Pandl, an economist at Nomura Securities International in New York.

About 48,000 temporary workers for the decennial census were hired last month, while private payrolls jumped 123,000, the highest since May 2007.

Employment last month was also lifted by a snap back from February's weather-related losses. Since December 2007, payrolls had contracted every month except last November, January, and now March.

The bounce back in employment could take some pressure off Obama, who has made putting back Americans to work a top priority. Since the start of the downturn about 8.2 million jobs have been lost.

Analysts reckon the state of the job market will determine when the Federal Reserve will start raising benchmark interest rates, which are currently near zero.

The U.S. central bank has promised to keep overnight rates ultra low for an extended period, citing subdued inflation and the likelihood the economic recovery will be moderate.

In the goods-producing sector, manufacturing added 17,000 jobs in March and construction payrolls grew 15,000. Payrolls in the services sector increased as retail employment climbed 14,900. Government employment increased 39,000, reflecting the temporary hiring for the census.

The average workweek for all employees rose to 34 hours from 33.9 hours in February.

(Reporting by Lucia Mutikani; Editing by Neil Stempleman)