U.S. adults aged 18 to 25 — who are now allowed to stay on their parents’ plans until age 26 because of a provision of the 2010 healthcare law — are less likely to be uninsured than in previous years. The percentage of uninsured declined further in 2011 to 24.5%, from 27.6% in 2010 and 28.2% in 2009. Although this group is still among the most likely to be uninsured, it is the only group Gallup tracks that has seen a significant decline in the percentage uninsured in 2011.

Hispanic Americans continue to be the most likely to be uninsured, with more than 40% going without health coverage in 2011, the highest Gallup has found for any key group since it began tracking in 2008. More than 30% of low-income Americans were uninsured in 2011 — a figure that has been rising since 2008, when it was 26.4%.

High-income Americans and seniors — two groups among the least likely to be uninsured — have not seen an increase in the percentage uninsured over time.