The Affordable Care Act’s health insurance co-ops absorbed deep financial losses last year, and 2016 is shaping up to be a make-or-break year for these nonprofit alternatives to traditional insurers.

Officially called Consumer Operated and Oriented Plans, these still-fledgling insurers were devised during the ACA’s creation to inject competition into insurance markets. But they have struggled from the start to build a customer base from scratch and deal with higher-than-expected expenses, among other problems.

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