The number is trotted out so often to make a point that it’s become unambiguous: Women in the U.S. earn about 79 cents for every dollar that men do. But recent studies paint a more nuanced picture of the wage gap.

Taking into account several factors, the difference could be just pennies, the studies, from think tanks on different places on the political spectrum, found. Women may make less because they decide to work fewer hours, or because scarce child-care options give them no choice. Some are blocked out of jobs by physical abilities and education. That’s not to say there isn’t discrimination, the studies noted, though it’s responsible for a small part of the chasm.

Where opinions differ is on whether government should work to bring the genders’ aggregate pay in line, or just focus on rooting out illegal inequities.