The nation's uninsured rate has plunged to anew low as more consumers shop in Obamacare's exchanges, accordingto the latest Gallup statistics.

The uninsured rate among adults is now 12.9 percent, down from13.4 percent in the third quarter of 2014 and down significantlyfrom 17.1 percent a year ago, the new poll finds, marking a drop of5 percent since the individual mandate under the Patient Protectionand Affordable Care Act went into effect.

Though the uninsured rate has declined across nearly all keydemographic groups in year one of PPACA, the sharpest decline inthe uninsured has been among African-American and low-incomeAmericans. Among Hispanics—the largest population of the nation'suninsured—the rate has droppednearly 7 percent, but still remainshigh at 32.4 percent. And, pollsters note, across age groups, theuninsured rate dropped the most among 18- to 25-year-olds, fallingabout 6 points from a year ago.