Drivers for online platforms including Uber and Lyft are making less than half of what they did four years ago, even as more and more people are drawn into working for them.

A new report from the JPMorgan Chase Institute, based on payments directed to 2.3 million families, showed that average monthly platform earnings dropped considerably — by 53% — between 2013 and 2017.

These drivers made $783 per month in 2017 versus $1,469 in 2013.

In the first quarter of 2014, nearly half of drivers who work for on demand platform such as Uber and Lyft, earned $900 a month or more. However during the first quarter of 2018, less than 25% of drivers were able to earn more than $900, the report found.

A limitation of the report is that it only took into account monthly earnings as opposed to hourly earnings. The reason for this being that it was not possible for the researchers to extract hourly earnings data from customers’ bank accounts. “We observe when customers are cashing out, but we don’t know how much they have been working,” said Amar Hamoudi, senior research lead at the JPMorgan Chase Institute.

“These declines in monthly earnings among drivers may reflect the fact that the growth in the number of drivers could have put downward pressure on hourly wages; they may also reflect a potential decline in the number of hours drivers are driving,” the report stated.

“Regardless of whether the drop in earnings was caused by a fall in wages or hours or both, it indicates that driving has become less and less likely to replace a full-time job over the past five years, as more drivers have joined the market.”

Having said that, both Uber and Lyft disputed the findings of the study. “The fact that this study did not examine hourly earnings, the metric that drivers care most about, has resulted in misleading headlines,” said Adrian Durbin, senior director of communications at Lyft. “Had it done so, the results would have shown stable driver earnings in recent years.”

Uber made a similar point in a statement: “The study’s findings reinforce what we and many others have said for some time: that the growth in on-demand work is driven, in large part, by people who use platforms like Uber on the side. Given the growing share of people who use platforms like Uber only occasionally, a more appropriate metric to focus on would be hourly average earnings, which have remained steady over time.”

Taking into account fees as well as other expenses incurred, Uber drivers typically end up earning just $9.21 an hour, a different report published by Lawrence Mishel, a distinguished fellow at the Economic Policy Institute, a left-leaning nonprofit think tank based in Washington, D.C. found.

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In his research, Mishel said he has found that there has been an increase in the amount of Uber drivers over the course of four years who are driving fewer hours each week. “Driving for Uber has become much more of an ancillary earning activity,” he said citing data from his report which equates eight Uber drivers to one full-time worker.

For many drivers the flexibility that driving for ride hailing companies like Uber allot them is the reason why they are willing to accept lower wages as opposed to taking on a second job with set hours.