Humana Inc. has added its name to the list of mega-medical insurers to report big problems under ObamaCare.

The Louisville, Ky.- based company does not expect to make enough money this year in premiums from individual plans to cover what it will pay out in claims, according to a regulatory filing made last week with the U.S. Securities and Exchange Commission.

Humana, which is being acquired by Aetna Inc., said it is still trying to figure out how big the gap will be.

Even with subsidies to make coverage more affordable, many people who buy health insurance on the marketplaces spend more than 10% of their income on premiums, deductibles and other out-of-pocket payments, a recent study found. Among those hit hardest, the researchers said, are people who spend nearly a quarter of their income on health care expenses.

“There’s been a lot of talk about how high deductibles and out-of-pocket costs are in the Affordable Care Act, and a lot of anecdotes about that, and this [study] quantifies that in a more systematic way,” said John Holahan, a fellow at the Urban Institute’s Health Policy Center who co-authored the study.