Officials say a record 64,000 Puerto Ricans left the U.S. territory last year, the highest number in the past decade.

The island's Institute of Statistics said Thursday that the exodus represents a 31 percent increase from the previous year. Some 49,000 people left in 2013.

Officials said the percentage of empty housing units in Puerto Rico also increased from 20 percent to 22 percent between 2013 and 2014.

Puerto Rico is struggling with a nearly decade-long economic slump that has sparked an exodus to the U.S. mainland. The government has imposed new taxes, cut certain services and increased utility rates in an effort to generate more revenue as it struggles with a $72 billion debt the governor has said is unpayable and needs restructuring.