Much debate has surrounded the Affordable Care Act (AKA “Obamacare”) since the legislation’s health insurance markets went live late last year. Since that time some encouraging numbers have shown that the program is working, at least a little. In December 2.2 million Americans signed up for health insurance using either the Healthcare.gov website or a state-sponsored healthcare exchange site. Now it appears that Obamacare’s heath insurance mandate is having a significant effect on the percentage of Americans who are still without health insurance.

Gallup today released a new poll showing that 16.1% of U.S. adults were still without health insurance during early January. This represents a slight drop from the 17.3% who were still uninsured during December, but a much more significant drop from the 18.6% peak that number reached in mid-2013.

According to Gallup’s survey, unemployed Americans are benefitting most from the new legislation. The percentage of unemployed U.S. adults in January without health insurance was measured at 34.1%, down from the 40.8% who were uninsured in December.

Women are also becoming insured at a faster pace than men, with the percentage of uninsured American women seeing a nearly 2% drop from December to January. This is more than double the 0.6% drop in the percentage of uninsured for men during the same period, despite the overall percentage of uninsured women (14%, as of January) already being lower than that of men (18.3%).

Though these poll results seem to show that Obamacare is reducing the number of uninsured Americans, Gallup is cautioning that recent numbers may not represent a long-term trend. The percentage of uninsured Americans has been falling since mid-2013, possibly indicating that other factors are influencing health insurance coverage in the U.S.