There are now 29 laws across the country at the city and state level guaranteeing workers the ability to take paid sick days. That’s a huge change from a decade ago, when San Francisco was the only place to do so. Still, about 40 percent of American workers don’t have access to the benefit.

And according to a recent report from the Institute for Women’s Policy Research, those who make the lowest incomes and are therefore the least able to take an unpaid day off when they get sick are the least likely to get paid sick leave.

Many workers whose professions put them in direct contact with the public, such as personal care providers and food service workers, are also among the least likely to be able to stay home when they’re sick.