Among six Pennsylvania health insurers with at least $50 million in revenue last year from the individual coverage sold under the Affordable Care Act, only two collected more in premiums than they paid in claims, according to Pennsylvania Insurance Department data released Monday.

They were Independence Blue Cross and Aetna.

The results illustrate the disarray in the ACA insurance markets, as insurers have struggled to accurately price insurance for a population that has proven to be a moving target.

In aggregate, two Independence subsidiaries, QCC Insurance Co. and Keystone Health Plan East, collected $776 million in premiums on individual ACA plans in 2015 and paid $656.5 million in claims, leaving a margin for administrative expenses of $119.5 million.

Administrative expenses, however, totaled $140.3 million, meaning that Independence had a pretax loss of $21 million on the individual plans for the two subsidiaries, according to the insurance department data.

Independence, which is the only company offering individual plans on the ACA exchange for next year in Southeastern Pennsylvania, said the forms used by the insurance department count certain expenses differently than the Philadelphia company does in its financial reports.

Aetna, operating as Aetna Health Inc., had a pretax profit of $13.6 million on individual ACA plans in 2015,  collecting premiums of just $71.4 million, while paying $52 million in claims.

Aetna said in August that it would no longer sell individual health insurance plans on the ACA exchange in Pennsylvania and 10 other states. Consumers must buy plans on the exchange to be eligible for a federal subsidy. In Pennsylvania, Aetna will stay in the market for individual plans bought  directly from the company or through brokers.

Highmark Blue Cross Blue Shield, by contrast, was in a $202 million hole before taking administrative costs into account. Highmark, based in Pittsburgh, collected $715.9 million in premiums, but paid $917.6 million in claims. It's total pretax loss was $290 million.

Others that paid more in claims than they collected in premiums were Geisinger Health Plan and a unit of Blue Cross of Northeastern Pennsylvania, which Highmark acquired in June of 2015.

Pricing in the small-group market was much easier for insurers to gauge.

In the small-group market, more companies than not  had a pretax profit, and all but four managed to collect more in premiums than they paid in claims.