The question of how much Uber drivers make per hour is always ripe for discussion. The number is hard to pin down for many reasons, including:

Uber pays different rates in different markets
A lot of driver income is tied up in limited-time promotions and incentives
Uber has repeatedly changed its commission structure and, consequently, how drivers are paid
Drivers bear costs like gas and depreciation, which must be deducted from gross earnings
Uber controls all the data
Uber has shared some numbers about driver earnings in economic papers, usually through collaborations with respected academics. But the figures it’s given out are hard to compare with one another. A January 2018 paper that Uber collaborated on used “gross earnings” ($21.07 an hour), or what the driver makes before costs such as gas and vehicle depreciation, as well as Uber’s service fee, are deducted. Earlier research from Uber’s team and Princeton economist Alan Krueger examined earnings “net of Uber’s fees,” but before driver expenses ($20.19 an hour).

Back in March, a study from MIT’s Stephen Zoepf claimed that the median profit from driving for Uber or Lyft was $3.37 an hour. The methodology behind this assertion proved seriously flawed, and after identifying the error and redoing the calculations, Zoepf increased his estimate of median hourly driver profit to between $8.55 and $10.

The latest contribution to the debate comes from the Economic Policy Institute (EPI), a pro-labor think tank. On May 15, EPI released a report finding Uber drivers earn $11.77 an hour after Uber’s commission and expenses, and $10.87 an hour adjusted for the extra contributions that independent contractors make toward Medicare and social security. That puts Uber drivers solidly in the lowest fifth of American earners.

“It’s more low wage than I thought, to tell you the truth,” said Lawrence Mishel, a labor economist and former EPI president who authored the report. “My sense is that taxi driving used to be an occupation that provided a very modest middle class income, and that just doesn’t seem to be the case any more.”