The lone health insurance cooperative to make money last year on the Affordable Care Act's public insurance exchanges is now losing millions and cutting off individual enrollment for 2016.

The lone health insurance cooperative to make money last year on the Affordable Care Act's public insurance exchanges is now losing millions and cutting off individual enrollment for 2016.

Maine's Community Health Options lost more than $17 million in the first nine months of this year, after making $10.9 million in the same period last year. A spokesman said higher-than-expected medical costs have hurt the cooperative.

The nonprofit's announcement casts further doubt on the future of insurance cooperatives devised during the ACA's creation to inject competition in insurance markets. These co-ops immediately struggled to build their businesses. More than half of the 23 created have already folded.

An Associated Press review of financial statements from 10 surviving co-ops shows that each has lost millions so far this year.