A record 64,000 Puerto Ricans left the island last year for the U.S. mainland, the highest number in the past decade, officials said Thursday.
The exodus represents a 31 percent increase from 2013, when some 49,000 people left, according to the island's Institute of Statistics.
The surge in departures comes as the US territory of 3.5 million people struggles with a nearly decade-long economic slump. The island has a 12 percent unemployment rate, higher than any US state, and has a labor participation rate of less than 40 percent, compared to 62 percent on the US mainland.
Overall, more than 200,000 people are estimated to have left Puerto Rico between 2010 and 2014, the majority of them families and young educated workers, local demographer Raul Figueroa said in a phone interview.
"Migration is accelerating," he said. "The government has to take this issue seriously."
Puerto Rico's government has imposed new taxes, cut certain services and increased utility rates, among other things, to cut costs and generate more revenue as it struggles with a $72 billion debt that the governor has said is unpayable and needs restructuring.
It is those measures that are driving people away, Mr. Figueroa said.
"We built up a massive debt when the population was still growing and young," he said. "Now we have to pay it when the population is dropping and becoming older."
As a result of the population loss, the percentage of empty housing units in Puerto Rico increased last year from 20 percent to 22 percent, according to the Institute of Statistics.
Gov. Alejandro Garcia Padilla said earlier this month that Puerto Ricans have sacrificed too much amid the economic crisis and that it is time for bondholders to come to the table.
Public Affairs Secretary Jesus Manuel Ortiz said Thursday that the government is in danger of running out of money by year's end if certain measures are not taken.
"We have to sit down and negotiate the debt to restructure it," he said. "On the contrary, all consequences will be very serious."