12.9 Percentage of uninsured American adults in the fourth quarter of 2014
13.4 Average percentage of uninsured U.S. adults in the third quarter of 2014
17.1 Percentage of uninsured Americans a year ago
4.2 Percentage points the uninsured rate has dropped since the Affordable Care Act went into effect one year ago

Source: A January 7, 2015 Gallup poll