Spoiler alert: not $90,000 a year. Getty / Oli Scarff Last year, Uber claimed its full-time New York City UberX drivers were making a median wage of about $90,000 a year.

Drivers responded by telling Business Insider's Maya Kosoff that they were often making less than minimum wage, with yearly earnings in the range of $10,000 to $41,000.

When UberX arrived in Philadelphia, Emily Guendelsberger, a senior staff writer at the Philadelphia City Paper, became curious about how much drivers would make.

So in January, she went undercover.

In an article in the Philadelphia City Paper, she explains that on her first trip as a driver, the money looked good:

As I let him off at 30th Street Station, he waves goodbye and thanks me, and says he's rating me five stars. The fare pops up on my phone: $10.85. The price of almost two beers for 15 minutes of driving! And if my neighbor had taken a cab, with tip, it would have been an even $20.

But in the long run, Guendelsberger found that the numbers didn't add up. One reason was Uber's massive fare cut, which took place just before she started driving. And since UberX drivers aren't licensed with the company and use their own cars, expenses such as insurance and gas add up, while the car's value depreciates.

Over the course of 100 rides, her hourly rate averaged out to $17. But after subtracting the 28% cut that Uber takes and 19% for car-related expenses, her actual pay ended up being $9.34 an hour.

She writes:

Driving for UberX isn't the worst-paying job I've ever had. I made less scooping ice cream as a 15-year-old, if you don't adjust for inflation. If I worked 10 hours a day, six days a week with one week off, I'd net almost $30,000 a year before taxes.

But if I wanted to net that $90,000 a year figure that so many passengers asked about, I would only have to work, let's see ...

27 hours a day, 365 days a year.

Though Guendelsberger concludes that Uber's business model isn't good for drivers, she admits that passengers benefit from the company's massive growth.

Not only is the service better than with traditional taxi companies, but the prices are generally lower, too.

"Whatever my reservations about Uber as a driver, it really, really is better for riders," she writes.

Read Guendelsberger's full article for the Philadelphia City Paper.