(AP photo/Jon Elswick)

The percentage of uninsured Americans remains unchanged from a couple of months ago, but remains at its lowest rate, holding steady at 13.4 percent.

Gallup released the data Thursday. The polling firm said the percentage of adults lacking coverage in the first two months of the second quarter of 2014 is down from 17.1 percent in the fourth quarter of 2013 and from the 15.6 percent average in the first quarter of 2014.

The 13.4 percent that’s held since April is the lowest Gallup has recorded since it began collecting the data in 2008. Researchers say the drop is largely attributable to the Patient Protection and Affordable Care Act (PPACA).

See also: Uninsured rate at lowest level since 2008.

“This rate, however, clearly shows a leveling off of the uninsured rate compared with the month-by-month declines seen in previous months,” Gallup researchers said. “It remains to be seen if the uninsured rate will stay at this level, increase, or decrease between now and mid-November, when the next open enrollment begins.”

Gallup found that across nearly every major subgroup, the uninsured rate is lower now compared with the fourth quarter of 2013. Uninsured rates dropped most among blacks — falling 6.2 percentage points to 14.7 percent — and Hispanics, down 5.6 points. However, with a 33.1 percentage uninsured rate, Hispanics still remains the most uninsured among key subgroups.

Younger adults—those 26 to 34 years old– continue to have the highest uninsured rate among all age groups at nearly 30 percent. Their participation is often viewed as critical to holding down health insurance costs.

Data is based on more than 30,400 interviews with Americans from April 1-May 31, as part of the Gallup-Healthways Well-Being Index.

Gallup said the uninsured rate could drop further if more states choose to expand Medicaid. But on the other hand, the rate could rise if newly insured Americans do not continue to pay for their insurance on an ongoing basis.