WASHINGTON » In a long-awaited surge of hiring, companies added 243,000 jobs in January — across the economy, up and down the pay scale, and far more than just about anyone expected. Unemployment fell to 8.3 percent, the lowest in three years.

The job growth was the fastest since last March and April. Before that, the last month with stronger hiring, excluding months skewed by temporary census jobs, was March 2006.

The unemployment rate came down by two notches from December. It has fallen five months in a row, the first time that has happened since 1994, two economic booms and two recessions ago.

"The economy is growing stronger," President Barack Obama said. "The recovery is speeding up."

Indeed, the report Friday from the Labor Department seemed to reinforce that the nation is entering a virtuous cycle, a reinforcing loop in which stronger hiring leads to more consumer spending, which leads to even more hiring and spending.

On Wall Street, where investors had already driven stocks to their best start in 15 years because of optimism about the economy, the jobs report triggered a spasm of buying.

The Dow Jones industrial average climbed 156.82 points, its second-best showing this year, and finished the day at 12,862.23, its highest close since May 2008, four months before the financial crisis struck.

The Nasdaq composite index finished at its highest level since December 2000, during a steep decline after the dot-com stock craze. Money poured out of bonds, which are considered less risky than stocks, and bond yields rose.

"Virtually every economist on the planet had expected a drop in the rate of job gains in January, which makes today’s upward surprise even more surprising," Dan Greenhaus, chief global strategist at the brokerage BTIG, said in a note to clients. In December, 203,000 jobs were created.

The impressive jobs report reverberated through the presidential campaign and could improve Obama’s re-election prospects. The drop in the unemployment rate put it exactly where it was in February 2009, the month after Obama took office.

Unemployment was 6.8 percent when Obama was elected, 7.8 percent when he was sworn in and 10 percent, its recent peak, nine months later. No president since World War II has won re-election with unemployment higher than 7.2 percent.

Employers have added an average of 201,000 jobs a month the past three months. That’s 50,000 more than the economy averaged each month last year.

Still, 11 million people either have stopped looking for jobs or are working part time and would rather work full time. When those people are added to the 12.8 million unemployed, nearly 24 million are considered underemployed. The so-called underemployment rate edged down in January to 15.1 percent from 15.2 percent.