WASHINGTON (AP) — A closely watched survey says the nation's uninsured rate dropped modestly this month as the major coverage expansion under President Barack Obama's health care law got underway.

The Gallup-Healthways Well-Being Index finds that the uninsured rate for U.S. adults dropped by 1.2 percentage points, to 16.1 percent.

The biggest change was for unemployed people, at a drop of 6.7 percentage points.

That was followed by a 2.6 percentage-point decline for nonwhites.