They've had reasons to pull back lately.
First came news of falling retail sales in March, then a series of weak manufacturing reports and signs of an economic slowdown in China.
Other reports, including two out Friday, have pointed to a slowdown. Factory orders sank in March and a gauge of growth in the service sector fell short of estimates.
First-quarter earnings have been mixed, too. Though they've come in higher than expected, many companies have reported little or no revenue growth, which has spooked investors.
Investors have also been concerned that higher Social Security payroll taxes and sweeping government spending cuts that took effect earlier this year will slow U.S. economic growth, and pinch corporate profits.
Friday's jobs numbers suggested the private sector might be strong enough to overcome those obstacles.
In its report, the government revised its previous estimate of job gains up to 332,000 in February and 138,000 in March. The economy has created an average of 208,000 jobs a month from November through April â¿¿ above the 138,000 added in the previous six months.
"Jobs are key," said Randall Warren, chief investment officer of Warren Financial Service in Exton, Penn. "Everyone is worried about things like fiscal policy, the government spending money it doesn't have. If you want to turn that situation around, you have to get people off their couches."
On Friday, on market's gains were broad. Eight of the 10 industry groups in the S&P 500 index rose. Nearly three stocks rose for every one that fell on the NYSE.
Companies that stand to benefit most from an upturn in the economy led the market. Those that make basic materials and produce oil and gas rose the most in the S&P 500 index.
U.S. Steel rose $1.08, or 6.3 percent, to $18.14. General Electric rose 25 cents, or 1.1 percent, to $22.57. Dow Chemical rose 84 cents, or 2.5 percent, to $33.96.