WASHINGTON (AP) — Federal Reserve Chair Janet Yellen said Monday that college graduates are entering the strongest job market the country has seen in nearly a decade, and their degree is more important than ever.

Yellen said that with changes in the job market such as technology and globalization, succeeding in the job market is increasingly tied to obtaining advanced degrees.

"Those with a college degree are more likely to find a job, keep a job, have higher job satisfaction and earn a higher salary," Yellen said in remarks at commencement ceremonies at the University of Baltimore.

She said that annual earnings for college graduates last year were on average 70 percent higher than those with only a high school diploma. Back in 1980 that difference was only 20 percent, she said.

Yellen said the increasing demand for people with college and graduate degrees reflected the need for higher technological skills and the impact of globalization, which allows goods and services to be produced anywhere. She said those trends were likely to continue.

"Success will continue to be tied to education, in part because a good education enhances one's ability to adapt to a changing economy," she said.

In her remarks, Yellen did not make any comments about Fed interest-rate policies. The Fed last week boosted its benchmark rate by a quarter-point. It was the first increase in a year. In making the announcement, the Fed projected that it would move rates up another three times in 2017.

Yellen said that in addition to the improvement in the unemployment rate, which in November fell to a nine-year low of 4.6 percent, there have been recent signs that wage growth is picking up.

But Yellen noted that challenges remain.

"The economy is growing more slowly than in past recoveries and productivity growth, which is a major influence on wages, has been disappointing," she told the graduates.