Aetna Inc. will again scale back its presence in the Affordable Care Act exchanges in 2018, saying it expects losses on the business this year.

Individual plans are a small share of Aetna’s overall business, and the insurer had already scaled back its exchange presence to four ACA marketplaces currently, down from 15 last year.

Aetna said it expects 2017 losses on its individual business will amount to roughly half its loss last year, which was $450 million.

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