If Not Uber, Who's Responsible for This Traffic?

In the recent dustup between Mayor de Blasio and Uber, the key battle was over what is slowing Midtown's traffic — but congestion numbers are hard to pin down.

Average speeds below the park dropped by 9 percent since 2010, from slow, to slightly slower. The New York Times tried to find out if Uber was really to blame.

"We were able to estimate that Uber vehicles contribute about 10% of traffic in Manhattan south of Central Park during the evening rush hour," said Jeremy Merrill, a reporter for the Times.

But that doesn't mean 10 percent more traffic. Certainly some existing black car drivers became drivers for Uber, and any Uber trip might be replacing what would otherwise be a taxi trip.

And there are other questions about Uber cars: Do they generally circle like a taxi? or park and wait? Only Uber knows, and the answer has an impact on traffic.

But so do a lot of other things.

The economy's better, which means more construction blocking lanes, more delivery trucks, more tourists. There's a new citywide speed limit, too, which could be slowing drivers down.

The city will be getting more complete data from Uber, including pickup and drop-off locations, routes and speeds. That information might shed new light on where the blame really belongs.