How Many New Yorkers Bike Each Day?

pucher_graphic_credit.jpgThe explosive growth in cycling across NYCDOT’s screenline tracks closely with rising bike commute rates among Brooklyn residents, but not with the slower citywide growth trend.

There were two developments today spotlighting the evolution of cycling in New York City. Transportation Alternatives came out with their updated figure for the number of people who bike in the city each day, an estimate that has climbed to 236,000. And a team of researchers led by Rutgers University professor John Pucher released their long-awaited study, "Cycling in New York City: Innovation at the Urban Frontier" [PDF]. While both point to a significant rise in cycling, the Pucher paper makes much more sober assessments about cycling growth than TA’s claim that the number of daily cyclists now exceeds 200,000.

The Pucher paper is a broad survey of cycling trends in New York, focusing heavily on what’s happened since 2000. It covers a lot of ground about who bikes, how much cycling has increased, what’s behind the rising popularity of cycling and what’s holding New Yorkers back from biking more. (We’ll have more on the report later — you should really read the whole thing.) The daily cyclist count from TA is a calculation that’s updated every year, based mainly on data from NYCDOT’s screenline counts, which record the number of cyclists who cross the East River bridges and 50th Street on the Hudson River Greenway, as well as bike commuters who take the Staten Island Ferry.

Both sources show a city where cycling is on the rise, but the Rutgers authors refrain from extrapolating citywide bike ridership. In fact, one of the Pucher team’s major points is that the screenline count is an imperfect basis for approximating total cycling volume, and that New York City needs a better way to gather information on bicycle travel.

Pucher is highy skeptical of the 236,000 figure calculated for TA by transportation analyst (and Streetsblog contributor) Charles Komanoff. Because the screenline captures cyclists in downtown Manhattan and northwest Brooklyn — where, according to census data, bike commute rates are the highest — extrapolating citywide bicycling rates from it involves a lot of uncertainty. "All of us agree that
there’s been big increases in cycling," said Pucher. But, he added, "there’s so many assumptions that you can question" in the TA estimate.

When I spoke to Komanoff this afternoon, he said some components of his formula, which hasn’t changed much since 1992, should be re-examined and updated.

So is there a better way to calculate how many people ride a bike in New York City each day?

Well, there are big flaws with the other data that’s out there too — which mainly consists of travel surveys conducted by the U.S. Census Bureau. The problem with travel surveys, said TA’s Wiley Norvell, is that bike trips get undercounted. "Secondary modes get discounted," he said. "There’s a lot of auxiliary and incidental travel that isn’t included."

In other words, because the census survey only counts your "primary mode" of getting to work, if you bike to the train or the bus, that won’t get counted as a bike trip. If you bike to work once or twice a week, you won’t show up in the census data as a bike commuter at all. Trips to the store or to visit family or friends don’t get counted, and neither do recreational rides.

Pucher said the shortcomings of census data are as exasperating as the screenline count’s deficiencies. His team looked at the three-year average from census surveys in 2006, 2007, and 2008. That yielded an estimate of 25,000 New Yorkers who primarily commute by bike. "There’s just no question that the data understates total cycling," Pucher said. In addition to undercounting non-commute bike trips, he said, the census undercounts cycling by the city’s enormous immigrant population.

Data from a different survey — the National Household Travel Survey — should provide a clearer picture of bicycling rates in New York, because it counts a wider variety of bike trips than the census. The detailed New York State NHTS data for 2009 hasn’t been released yet, however, and prior to last year the survey hadn’t been conducted since 2001. Pucher is itching to get his hands on the new numbers.

When I asked Pucher to hazard an estimate of the total daily cycling figure for New York City, he hesitated to name a number. Eventually he sketched out a range. "The percentage of work trips by bike is maybe a third or a half of the total," he said, referring to a rule of thumb among bike planners. So using the census number — 25,000 daily commuters — there are at least 50,000 bike commute trips and thus 100,000 to 150,000 total bike trips each day, Pucher said. After factoring in all the ways the census undercounts cycling, he was willing to venture that the number of trips is somewhat higher than that. (Note that we’re talking about trips, not individual cyclists.)

Pucher’s underlying point — and, I suspect, the reason he was reluctant to give me an estimate — is that New York City lacks the data to really understand how many cyclists are using its streets. "The bottom line is, we need a better survey," he said. "In Portland, every single year, they have travel surveys, broken down by mode,
gender and age. Why don’t we have that in New York City? It’s something that
NYMTC [the New York Metropolitan Transportation Council, the agency that plans how to spend federal transportation funding] should be doing. It’s really the fault of the metropolitan planning organization for not having
conducted the right kind of survey, that does include work trips and
non-work trips, and covers all different parts of the city. Above all it will help determine where we build facilities and what types we build."

A more rigorous approach to measuring bicycling would help guide decisions about bike infrastructure, Norvell agreed. "The complexity
and depth of knowledge we have of driving behavior is part of the
reason driving is so heavily subsidized," he said. "If we knew more about the way
cyclists behave, we’d know more about where to invest in cycling
infrastructure."

One thing the screenline counts definitely tell us, said Pucher, is that recent investments in bike infrastructure in the Manhattan core and near Brooklyn’s East River bridges have paid off. "It does confirm that the state-of-the-art facilities in lower Manhattan
and northwest Brooklyn, that they’re certainly well used," he said. "That’s a vindication
of DOT’s policies."

  • 1. The city needs to figure out a way to do a more comprehensive count.

    2. T.A’s gotta stop putting out this number! It’s so incredibly far from reality that it’s going to start to hurt the credibility of their other studies and reports, which are crucial and often very high-quality.

  • BicyclesOnly

    Great post, Ben. Looking forward to further analysis of the article’s findings.

  • Bill Lee

    If the analyst and group which produced this whopper 236,000 number agree it has problems why are they issuing press releases about it? This is hype. The professor is trying to say the real number is less than half that.

  • Clarence Eckerson Jr.

    Whatever you believe about the number, I have been riding in NYC since ’92 and it is unbelievable the numbers of cycling now. I used to get jealous of seeing the squadrons of commuters riding over the Hawthorne Bridge (Portland) and on Market Street (SF). But not any more, we’ve got our own heaps of commuters on Bergen Street, all the East River Bridges, the West Side Highway Bike Path, just to name a few – on a weekend the Kent Avenue new two-way path is crowded with cyclists.

    So I agree: it is time to finally do as accurate count as we can get. I do think the T.A. number is high, but what I would truly like to see is what Portland does – I’d love to see what the neighborhoods commute rate is. In Portland they have some neighborhoods that are in the 15 to 20% range. While it would be hard to find that in NYC, I am absolutely convinced there are some parts of Williamsburg, Greenpoint, the Lower East Side, Park Slope, Carroll Gardens, LIC, where there are 5 to 10% commuting rates on non-Winter days.

    NYC is a huge place. Staten Island, and the far reaches of the Brooklyn and Queens must have extremely low commute rates (not hating, just saying). So when stats say NYC commute rates are at about 1%, that doesn’t do us much justice. We need to have solid numbers for communities, and that will justify the bike infrastructure even more.

  • BB

    Look to Denmark, they know how to count cyclists daily.

  • Why does the chart show relative increases and not absolute numbers? It’d be a lot more informative to show the number of cyclists in each borough, not the percentage increase since 1990.

  • Larry Littlefield

    A survey of about 3,000 households ought to be enough to get a citywide estimate, if one discounts the bias that bicycle riders are more likely to answer the survey. One can get around that by asking first if anyone in their household has a bicycle, and limiting the number of follow up questions.

    Additional survey numbers would be required to stratify the sample, and get reasonably accurate estimates of bicycle use for sub-groups, and by category of use (deliveries, recreation-exercise, transportation to destination type).

    It may be possible to conduct such a survey as a hybrid — supervised and spot checked by a market research company, and conducted by volunteers and/or students interested in the field.

  • Alon, it’s because the absolute numbers are pretty tiny. That’s common with “bicycle boom” reports. I honestly don’t think it does much for cycling to exaggerate the impacts like that.

  • To me, the absolute number of cyclists each day is beside the point because (1) it is impossible to know with accuracy and (2) the most important thing is the trend, and the census and the screenline counts are pretty much showing the same trend.

    As Pucher suggests, there likely is a substantial population of daily cyclists who live in the Bronx, Brooklyn and Queens who very rationally conclude that cycling for transport provides better value than up to $2.25 each way for lousy mass transit services. Except for those who enter Manhattan south of 50th St. or answer a census inquiry, this population would not show up in either the Komanoff or the census figures.

    The potential size of this uncounted population is hinted at in Figure 3 (on page 4) of the Pucher paper, which reports the census findings by region of the city. Given Pucher’s findings that cycling rates do not vary materially with income, ethnicity and citizenship, and the continuing centrality of CBD employment, one would expect a relatively even falloff in commuter cycling rates as one moved outward from the Manhattan CBD (perhaps with variations reflecting availability of bike infrastructure). Yet Central Bronx reports up to 1% bike as primary mode of commutation–three to four times the rate of every surrounding Bronx neighborhood except the South Bronx–which itself still has a lower rate than Central Bronx. Why is that?

    Similarly, the Rockaways are reporting the highest level of bike as primary commutation mode in Queens–the same rate as Long Island City. How can that be?

    One answer is that there is systematic underreporting on the census of bike commuting in the outer boroughs, and that (for some reason), the underreporting is less severe in Central Bronx or the Rockaways. If this is true, then it may well be that a number of the more remote outer-borough regions on the map have actual cycling rates more like Central Bronx and the Rockaways. That would mean that the census undercounts cycling in these regions by up to 300%. Even though these regions are less densely populated than Northwest Brooklyn and Manhattan, there are many of them, and I suspect the undercounted commuter cyclists in them could easily fill the gap between the Pucher and Komanoff estimates. (I don’t know if Komanoff attempted to adjust for this census undercounting in the outer boroughs in his citywide extrapolation, but if he did, it could account for the difference).

    Obviously, I’m speculating. The point is that the Komanoff and the census figures also have numerous speculative aspects or potential errors built in. To me, the pursuit of the “true” number of daily cyclists is fundamentally quixotic. The key is the 20%+ increase year, after year, after year, since JSK came in as DoT Commish. If we can keep that going, we’ll be at 200K+ daily bicycle commuters in no time, by all accounts.

  • Larry Littlefield

    “One would expect a relatively even falloff in commuter cycling rates as one moved outward from the Manhattan CBD (perhaps with variations reflecting availability of bike infrastructure).”

    I would expect substantial bike commuting by immigrants from places where it is more common, living and working in the same borough, with the trip between the two points not served by a single transit line. Only a survey would capture that, perhaps door to door to capture those who have cellphones rather than landlines.

  • flp

    why do so many assume that there are lower number of cyclists in the outter reaches of the outter boroughs? of course there may be a lower number heading into the manhattan cbd, but that is not the only destination! aside from those commuting long distances to work, most cyclists likely are those who make shorter trips within their neighborhoods or boroughs. all the counts that have been implemented so far seem to greatly miss those cyclists except of course those who are doing those short trips within the manahattan cbd. in fact, i bet that cycling has always been quite high in the outter boroughs due to the desire to reduce transportation expenses.

  • Shemp

    Pucher article seems like a reasonable assessment though mistakes parking-protected bike lanes on Kent Ave. and Grand Street for “buffered” bike lanes.

  • J:Lai

    I would guess that there are a lot of immigrant groups that are underrepresented, and that many are concentrated in the outer boroughs where they use bikes to get to and from jobs not located in manhattan cbd.
    (and in some cases to perform those jobs, such as deliveries for take out restaurants.)

  • Ace

    http://www.streetsblog.org/2009/11/09/count-on-it-nyc-bike-commuting-climbs-26-percent/

    DOT Commissioner Janette Sadik-Khan touted these improvements in announcing the new stats. “Cycling in the city continues growing rapidly as our bike network expands and becomes safer,” she said in a statement.

    The agency measures bike commuting by counting cyclists crossing 50th Street on the Hudson River Greenway, riding over the four East River bridges, and entering and exiting the Staten Island Ferry at Whitehall Terminal. Notably, cyclists riding across 50th Street on the avenues are not included in the count.

    DOT staff tallied an average of 15,495 cyclists crossing this zone on weekdays between April and October this year. On one day in August, the bike count reached a peak of 18,223 cyclists.

  • On average, I make a handful of discreet bike trips every day, all within Brooklyn. And I doubt I show up in anybody’s count.

  • Andrew

    Maybe if you weren’t so discreet about it, you’d be counted!

  • Sid Ereal

    The relatively higher representation in the central Bronx might not be so perplexing given the impact of Fordham on the data. The students and much of its staff probably represent not only a disproportionate number of bicyclists in the Bronx, (with a University-driven travel focus, distinct from the Manhattan CBD), but Fordham U‘s population is going to be far more approachable and surveyable than almost any other by the census, due to the ease of outreach through the University (people who are infirmed and people who are incarcerated may be easy to count, but their use and access to bikes don‘t much factor into the stats). Almost all other similar sized Universities in the city are already counted within the high bicycle traffic zones of NW Brooklyn and Manhattan (St. John‘s may be an exception, in leafy Central-North East Queens, which is low density, middle-income and has higher than city average motor vehicle ownership). Rockaway is curious, especially given its harsh, windy and ill-paved winter. Practically though, mass transportation on the 10 narrow miles of the Peninsula is surely no faster or more convenient than a bike in good weather, and the Rockaways do lend themselves -with wide boulevards, a somewhat tame traffic pattern with comparably little cross traffic, miles upon miles of Boardwalk and sparse and distant retail- to the advantages of the bicycle. Worth noting is that,in good weather, the Rockaways are also a main bike enthusiast destination from throughout South and S.E. Brooklyn, via the Belt Pkwy greenwy. The two most ridable places in Brooklyn for anyone training on a bike are going to be the Prospect Park loop and the much longer Belt Pkwy Greenway, which is typically in very good condition, is uniquely scenic and connects directly with the Rockaways by the Marine Parkway Bridge bike (really a pedestrian) path, and Cross Bay Blvd. But, its hard to deny that, while the Rockaways are without-a-doubt an intensive recreational bike choice in good weather for residents and visitors, one could imagine wind and winter makes the bike a foreboding alternative for many people for nearly 5 months out of the year.

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