Uber has been underpaying New York City drivers since late 2014 when it rolled out a new driver agreement, the company told the Wall Street Journal on Tuesday. Instead of calculating its cut after accounting for taxes and fees, Uber has been doing the math on the larger amount.

Uber says it will refund all affected drivers, including interest, which should amount to about $900 per driver on average. Overall, this will likely cost the company about $45 million, according to an estimate from the Independent Drivers Guild, which represents many NYC drivers.

Don't forget: This is far from the first time Uber's been in hot water over driver compensation. In the last few months, Uber has agreed to pay out $20 million to resolve a complaint to the FTC over its claims about driver pay, and has also admitted to underpaying black car drivers in Pittsburgh since 2015. Its "upfront pricing" approach has also been subject to much criticism for opaquely underpaying drivers.