Yet another insurer is leaving Obamacare because the marketplace isn't stable, a few days after Aetna announced it would pull out of two-thirds of its Obamacare market.

Texas insurer Scott & White said it will exit the Obamacare marketplace in the state next year.

"Like many other health insurers, we have determined that we cannot currently serve marketplace plans on an effective and financially sustainable basis," the insurer said Wednesday.

The company will offer some individual health insurance plans, but not on the Obamacare exchanges. The individual market is for people who don't get insurance through their work, and Obamacare comprises a majority of the market.

The decision means that residents in the nation's second-largest state will have to find a new plan when open enrollment starts in the fall. The insurer serves about 58 counties in Texas, according to the Dallas Morning News.

The insurer is the latest one to exit Obamacare next year due to financial troubles. Aetna announced late Monday that it would exit the exchanges in all but four states next year.

The decision follows decisions by Humana and UnitedHealth to pull out of some states.

The reason is financial losses that have increased due to a sicker-than-expected enrollment in Obamacare.

Scott & White hinted it was having the same problems, saying that Obamacare marketplace plans "carries higher risk than other plans."