The share of people without health insurance keeps falling.

Since 2013, when the major provisions of Obamacare went into effect, the uninsured rate has fallen in every state. And some states that you might not expect have led the way.

The news about the Affordable Care Act has been grim lately: The price of health plans in new marketplaces is up, and choice is declining in many places. But amid the difficulties, new data highlight the law’s effectiveness in getting coverage for millions of Americans.

Over all, the gains are substantial: a seven-percentage-point drop in the uninsured rate for adults. But there remain troublesome regional patterns. Many people in the South and the Southwest still don’t have a reliable way to pay for health care, according to the new, detailed numbers from a pair of groups closely tracking enrollment efforts. Those patterns aren’t an accident. As our maps show, many of the places with high uninsured rates had poor coverage before the Affordable Care Act passed. They tend to be states with widespread poverty and limited social safety nets. Look at Mississippi and Texas, for example.

But many of the places that have reduced their uninsured rates the most had similar characteristics in 2013. Look at Kentucky and Arkansas. Over the years, you can see them diverge sharply from their neighbors.