ACA premiums would probably be going down next year if the Trump administration and congressional Republicans had simply left it alone, Brookings' Matt Fiedler says in a new analysis this morning.

The big picture: Insurers are raking in money this year, largely thanks to the very large premium hikes they enacted. They'll likely see a profit margin north of 10% on their ACA business this year, up from just 1.2% last year and losses in the years before.

• Fiedler estimated what would happen if the regulatory status quo at the beginning of 2018 had carried over into 2019. In that world, cost-sharing payments would still be gone, but the individual mandate would remain in place and the expansion of short-term plans wouldn't have happened.
• In that hypothetical policy environment, insurers probably would have reduced their premiums by an average of 4.3% next year, he found.

Premiums are actually falling in a few markets.

• Louisiana is the latest. ACA premiums in the state will drop by an average of 6.4%, according to The Advocate.
• Average premiums in Minnesota are also set to decline next year, largely thanks to the state's reinsurance program.