Even banks are joining the Puerto Rico exodus, and their flightcould leave the island's financial system increasinglyisolated.

Not only did the number of consumer banks drop by half over thepast decade, but the main international players — Bank of NovaScotia and Banco Santander SA — have been quietly shrinking,leaving the field to local institutions.

As the commonwealth tries to emerge from recession and rebuild after last year's Hurricane Maria, ahandful of banks may wind up in charge of deposits and lending forits 3 million people, curbing competition that helps controlinterest rates. Popular Inc., First BanCorp/Puerto Rico and OFGBancorp are cash rich and have many branches, but limited abilityto facilitate trade beyond the Caribbean and Florida.