The numbers: Americans quit their jobs in May at the fastest rate since 2001, showing that workers feel so good about the economy they are willing to leave one company for another.

The percentage of people in the private sector who left their jobs by choice rose to 2.7% from 2.5%, the government said this week. The so-called quits rate among all workers edged up to 2.4% from 2.3%. Both hit the highest levels since 2001.

Most workers who leave jobs voluntarily end up getting better pay or benefits elsewhere. More people are willing to make the switch when the economy is booming.

Read:Workers still not earning big pay raises despite 4% unemployment. Here’s why.

Job openings, meanwhile, fell to 6.64 million in May from a record 6.84 million as companies filled more open positions.

What happened: Some 5.75 million people were hired in May, up 170,000 from the prior month. that’s also the biggest gain in hiring in 17 years.

About 5.46 million people lost their jobs in May, the Labor Department reported Tuesday.

Most the decline in job openings was concentrated in the highly populated Northeast. Opening for information-services such as media and public relations fell by 60,000. Arts and entertainment-related job openings also declined.

Big picture: The economy is surging. Companies are hiring rapidly to keep up with demand for their goods and services and soon the unemployment rate could fall to levels not seen since the 1960s.

Read:U.S. adds 213,000 jobs in June

As the rising quits rate shows, more workers are striking out for better jobs or better-paying jobs, confident they’ll succeed. If more workers do that, it could force companies to raise wages faster to retain their best employees or to attract new ones.

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While better pay is great for workers, it would also set off alarm bells at the Federal Reserve. Senior officials are watching closely to see if higher wages spur inflation, an outcome that would force the central bank to raise interest rates more aggressively.

Read:Trump set to make Supreme Court even more pro-business with Kavanaugh pick

What they are saying?: “The rise in the job quits rate points to wage growth accelerating to 3% by the end of the year,” said senior U.S. economist Michael Pearce at Capital Economics.