Is Uber Making NYC Rush-Hour Traffic Worse?

Uber has been taking passengers from taxis, one by one, on the busiest streets of Manhattan, as we wrote in October.¹ But is that shift in the city’s transportation habits consistent all day long, or are there peak periods when the new ride-for-hire service is adding more trips to the streets than taxis are losing? In other words, is Uber making congestion worse at some hours of the day?

That was the question asked by one of our readers, Kimberly Ziev Niehaus, in a comment she left on our October article.

It’s a good question because our previous analysis treated all rides the same, no matter what time of day they started. But congestion is a function of how many cars are on the road at the same time — not of how many there are at other times of day.² We looked more closely at the data we used in our earlier analysis, when we compared taxi and Uber pickups from April, May and June of this year with pickups in the same months a year earlier. We found that there were some subtle but meaningful differences in Uber and taxi usage by hour during a typical weekday.³

In the morning, Uber did not add extra trips to the streets in the area known as the Manhattan core — south of 110th Street on the West Side and 96th Street on the East Side. Uber added fewer rides than taxis lost during those hours, resulting in a net decrease in the number of trips by taxis and Ubers. But that picture changed in the evening rush hour, beginning at 4 p.m. During those hours, Uber added more trips than taxis lost. The total number of pickups for both services rose during the evening rush from 4 to 7 p.m. and again from 9 p.m. to 1 a.m.⁴

These increases weren’t enormous: The biggest change during busy hours was a 4 percent rise in pickups between 4 p.m. and 5 p.m. — or an average of 682 additional pickups per non-holiday weekday during that hour. For comparison, there are, on average, about 24,000 vehicles on all the roads in Manhattan’s central business district — the part of the island south of 59th Street, which is most of the core — at any time between 2 p.m. and 8 p.m. on weekdays, according to estimates made by transportation economist Charles Komanoff in his model of Manhattan traffic.⁵

Uber maintains that any increase it is generating in overall traffic is minimal.

“As I was over the summer, I’m still skeptical this is having an impact on congestion in a material way,” Josh Mohrer, general manager of Uber in New York City, said in a telephone interview. He pointed out that our analysis doesn’t consider whether Uber is replacing rides in private cars or by other ride-for-hire companies. “Uber is taking lots of cars off the road and will continue to do that,” he said.

The increase in total Uber and taxi pickups during evening rush hours and later at night wasn’t spread evenly between the two competing services. Instead, Uber pickups surged by more during that time than they did the rest of the day, while taxi pickups experienced their biggest drops.

One possible explanation for why Uber did better than taxis beginning at 4 p.m.: The yellow-taxi shift change between 4 p.m. and 5 p.m. That’s when drivers go off duty as they return their cabs to garages for fresh drivers. Perhaps some of the people who waited a long time to hail cabs during and just after the shift change last year switched to Uber as it added drivers in New York. It’s less clear why Uber took so many taxi rides even hours after the shift change.⁶

The picture is very different when you look outside the Manhattan core, in the other four New York City boroughs and northern Manhattan. In these areas, Uber added substantially to the number of for-hire vehicles on the street throughout the day.

Ubers increased pickups outside the Manhattan core, especially in the evening, presumably as more people heading home from nights out chose a car and driver over a bus or subway.

New York’s Green Cabs Stay Close To The City Center

Public Transit Should Be Uber’s New Best Friend

Uber Is Serving New York’s Outer Boroughs More Than Taxis Are

Footnotes

Data we received from a Freedom of Information Law request to New York City’s Taxi and Limousine Commission covering April, May and June of this year showed that compared with the same months a year earlier, Uber pickups in an area known as the Manhattan core — south of 110th Street on the West Side and 96th Street on the East Side — rose by 3.82 million, while taxi pickups fell by 3.83 million. That suggested, we wrote, that the new ride-for-hire service wasn’t adding to congestion in Manhattan, as New York City Mayor Bill de Blasio had suggested. Instead, we found that it was subtracting business from taxis.
Her other question is a good one, too — one we addressed in the article: “We don’t have data on dropoffs, on ride length, or on location of pickups by other services like Lyft, an Uber competitor, and established black-car companies.” It’s difficult to say how data for other companies would change the finding. Lyft and other new entrants to the market might be taking business from the established car-service companies. In any case, taxis and Ubers are the dominant ride-for-hire providers.
Our analysis covered the average non-holiday weekday, which, during the periods for which we had data, meant all weekdays besides Memorial Day. We included Ubers, yellow taxis and green cabs, though the green cabs aren’t allowed to make pickups in Manhattan’s core so they don’t materially affect the analysis for that part of the city.
We broke up the day into 24 hour-long periods, starting with midnight to 12:59 a.m.
We’re going to try to put these numbers into context, though the best we can do is a rough estimate because of data limitations. We don’t have the data we need to say exactly how much impact the additional pickups are having, for three reasons: 1) Komanoff’s estimates cover six-hour blocks, not single hours; 2) Our numbers cover Manhattan’s core while Komanoff’s cover the central business district (CBD), which has the majority of the core’s roads and traffic; and 3) He has average vehicle counts while we have pickups, which don’t directly correspond to the number of cars on the road at any one time. The New York Times estimated in July that about half of cars in Midtown during the evening rush are taxis or Ubers. If that was true from April to June and applies to the entire CBD, then there are about 12,000 Ubers and taxis on the road at any time from 2 p.m. to 8 p.m. — half of Komanoff’s estimate of the total of 24,000 vehicles on the road in the CBD. According to our data, Ubers and taxis averaged about 18,000 pickups per hour combined this spring between 4 p.m. and 5 p.m. in Manhattan’s core. Dividing 18,000 pickups by 12,000 Ubers and taxis suggests that taxis and Ubers make something like one or two pickups per hour. So if taxis and Ubers together added 682 pickups per non-holiday weekday between 4 p.m. and 5 p.m. in April-June 2015, compared with April-June 2014, they added just a few hundred cars to the core’s roads.
Taxis remained the dominant method of for-hire transportation in New York this spring, taking 84 percent of all pickups between 4 p.m. and midnight. But that’s down sharply from 95 percent a year earlier.

FiveThirtyEight

Is Uber Making NYC Rush-Hour Traffic Worse?

Footnotes

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