Census and City Bike Ridership Data Differ Drastically

04/13/2011 4:29 PM |

Bike commuters on Casual Friday.

  • Bike commuters on Casual Friday.

In an uncharacteristically even-handed bit of bicycle journalism, the Post looks at conflicting stats offered by the city’s bike lane-laying Department of Transportation and a new study from NYU’s Furman Center based on Census data that suggests bike ridership may have fallen.

Well, not really: as the Post soon figures out, the apparent drop in bike commuters “discovered” in the census data parsed by Furman Center statisticians results from the different criteria used there and in the DoT surveys. The census asked respondents how they got to work, but if they biked to work less than half the time and took the subway the rest, they were recorded as subway commuters.

Meanwhile the DoT actually stations surveyors at bridge bike ramp exits, at the Staten Island Ferry and along the Hudson River greenway ten times per year, so their figures pertain to all types of bike ridership—commuting, for work, recreational, etc. In doing so they tend to focus on bike-heavy neighborhoods in Manhattan and Brooklyn, which may distort data in the opposite direction of the census data. So comparing the two sets of data is a lot like comparing apples and isolationism.

On the other hand, other cities whose cycling inhabitants answered the census’s commuting question reveal that bike commuting rates in New York (about .6 percent of all commuters according to the census) are way behind Boston (2.2 percent) and bike-share-having Washington D.C. (2.3 percent). Maybe the forthcoming bike-share program will help us reverse the trend.