Since its debut last year, New York City's bike share system, Citi Bike, has been wildly popular. In its first six months of operation, the bright blue bikes logged more than 5 million trips. The system has nearly 100,000 annual members. Yet Citi Bike—which unlike most bike shares in major cities, isn't subsidized by public funds—is losing money. One of the main reasons is that while annual memberships are popular, the much more profitable day passes aren't. It's a phenomenon easily seen in this visualization of two days of Citi Bike rides around New York City.
Designer Jeff Ferzoco, Sarah Kaufman at New York University's Rudin Center for Transportation and Juan Francisco Saldarriaga of Columbia University's Spatial Information Design Lab worked together to visualize Citi Bike journey data from September 17 and 18 of last year. Over those two days, when the weather was in the 60s and there was no rain, Citi Bike saw 75,000 rides. Rides are separated by type of membership, either annual (blue) or casual (yellow).
The visualization doesn't show exact routes along the city's grid, but instead approximates trips by tracing straight lines between the endpoints. Ridership picks up early in the morning, around 5:30 a.m., and is heavy between 7 a.m. and 10 a.m. Almost all of those riders are annual members. Yellow dots are barely visible on the map, except a few around the very lower tip of Manhattan and up near Central Park. As the day wears on, there's a slight increase in casual members—people riding over the Brooklyn Bridge, for instance—but for the most part, the vast majority of the map is the blue. During the evening rush hours, when commuters get back on a Citi Bike to go home, the map is overwhelmed by a dense network of blue.
Interestingly, more riders seem to take Citi Bike during the evening hours than take it to work. The number of active riders hits 800 at 8:30 a.m., but spikes to more than 1,000 at 6 p.m.
Though the balance of ridership clearly tips in favor of annual membership, it would be interesting to compare this data to a weekend. Perhaps more people are willing to grab a daily pass on a Saturday than during the workweek.
[H/T: the New York Times]
[Image: Citibike via Flickr user Several Seconds]