The U.S. labor market is showing no signs of slowing down.

The unemployment rate fell to 3.6% — a 49-year low in April — and the economy added a whopping 263,000 non-farm payrolls, according to new data released by the U.S. Labor Department Friday. The unexpected jump in payrolls caught many economists off-guard, including Austan Goolsbee, former Chair of the Council of Economic Advisers under the Obama administration.

“It’s a little bit of a surprise and a nice surprise to keep getting big numbers like this so far into an expansion,” he told Yahoo Finance On the Move, noting that we’ve seen low unemployment for the past five years.

President Donald Trump touted the strong April jobs number on Twitter, writing:

But the surge in employment is being met with some skepticism. Analysts point to a shrinking labor force as the number of Americans who are working or actively searching for jobs fell for the second month in a row to 62.8%.

“The unemployment rate has gotten pretty low,” said Goolsbee. “We continue to bring more people in than expected and that’s been a pleasant surprise, but obviously can’t go forever,” he said. “Eventually population growth limits how many jobs you can add. The question is how much unobserved slack in in that number.”

Nick Rose is a producer for Yahoo Finance On the Move.

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