One Chart Brilliantly Sums Up Citi Bike’s Safety Record

Graphic: Tom Swanson
Graphic: Tom Swanson

Courtesy of GIS specialist Tom Swanson, this graphic contains the best evidence yet that Citi Bike has not led to an increase in bicyclist injuries.

Using crash information scraped from NYPD PDFs by freelance web developer John Krauss, Swanson was able to map which bicyclist injuries occurred inside the Citi Bike service area. Then he charted those injuries as a percentage of all cyclist injuries in the city. If Citi Bike was leading to a significant increase in injuries to cyclists, you would expect to see the percentage of cyclist injuries in the service area rise after bike-share launched at the end of May 2013.

Instead, Swanson’s chart shows that the share of injuries in the service area is holding steady. Compared to the same months in previous years, there has been almost no deviation from the pre-bike-share state of affairs. We already knew that very few people have been injured riding Citi Bike. Swanson’s chart adds citywide data that helps put that small number of injury crashes in context.

This is all the more remarkable when you consider that people have been making between 30,000 and 40,000 bike-share trips every day, so the bike-share zone almost certainly accounts for a significantly greater share of overall NYC bike trips now than it did before Citi Bike. With the share of bicycling increasing inside the bike-share zone and the share of bike injuries holding steady, Citi Bike is, if anything, making it safer to ride a bike. More evidence of safety in numbers.

Swanson’s charts do show that overall NYC bike injuries have gone up slightly in 2013. But that’s true outside of the Citi Bike zone as well as inside. It could be random fluctuation or there might be real underlying causes, but it’s not due to bike-share.

Graphic: Tom Swanson
Graphic: Tom Swanson
  • stairbob

    Another question is how much is cycling up overall? It may be that cycling is up, for example, 10%, but that injuries are up 1%, meaning that the average cyclist is safer than before. (Yes, these numbers are made up.)

  • A Pedestrian

    This is more pro-bicycle propaganda.

    Where is the discussion of pedestrian injuries caused by bicyclists riding on the sidewalk, riding against traffic, coming up from behind out of pedestrians’ blind spots, running through red lights, plowing into crowded crosswalks, riding without lights at night, etc.? I notice in one of the reports on “walking” on this site one man’s description of the problems we pedestrians encounter from the commonplace recklessness of bicyclists was trivialized as “ranting.”

    Answer: there is no discussion of pedestrian injuries, many of which do not result in a visit to the emergency room, but which can nevertheless be serious for older folks.

    And why is there no enforcement of traffic laws against bicycles, which are violated with impunity at every moment?

    It’s only about injuries to bicyclists. But for pedestrians — especially the elderly — bicyclists are the bad guys. The bicycle explosion has made the city unsafe for pedestrians, especially the elderly, the visually handicapped, the physically challenged.

  • els

    Not only is there no mention of pedestrian injuries but the sampling method is flawed. Not to mention that most injuries go unreported. Lousy methodology. lousy and sloppy science. Therefore erroneous conclusions

  • qrt145

    That falls outside the scope of this analysis, because, like you say, there is no good data about bike-pedestrian crashes. But it is an excellent response to the hysterical claims prior to the bikeshare launch that “inexperienced and unhelmeted” bikeshare users would be dropping dead like flies.

  • Joe R.

    If you bothered to read some of the other articles on this blog, you would find that cyclists are in fact ticketed for violations at a rate disproportionate to their numbers, including for nonexistent offenses like riding outside the bike lane. If you expect to be taken seriously, you need to stop making stuff up. If there was such a big rash of pedestrian injuries caused by reckless cyclists, surely we would be aware of it in both the media and the emergency rooms. Cyclists can and do get hurt when they run into pedestrians, often ending up with worse injuries than the person they run into. Therefore, it’s in our best interests to not hit pedestrians.

    No, what’s made the city unsafe for pedestrians and cyclists is motor vehicles. That’s what kills 200+ people per year in the city and injures thousands. That’s what causes many times this number to develop life-altering illnesses caused by pollution. Compared to this, reckless bicycle riders are a rounding error. Most cyclists aren’t reckless. Most of the overblown pedestrian-bicycle conflict comes because both modes are fighting for the scraps of space left over after we devote 90+% of the street space to motor vehicles.

    Also, while I’ll acknowledge that reckless cycling can result in pedestrian injuries, recognize that there are some pedestrians who just blindly wander in front of bikes with their heads buried in their gadgets. You never see them do this in front of motor vehicles, but somehow they feel it’s OK to do so in front of bikes. Respect is a two-way street. At least one member here crashed and had extensive dental work because of a errant pedestrian who wandered in his path when he had the right-of-way.

  • Ian Turner

    Perhaps instead of complaining, you should inject some data into the conversation.

  • Stats

    I’m not sure how it’s changed in the past few years, but in 2010 NYC residents who were 65 and older made up 12% of the population but 38% of pedestrian deaths caused by motor vehicles.

    The bicycle explosion has not at all made the city unsafe for those with limited mobility. Pedestrian islands, plazas, and bike lanes have made things far safer. Sidewalk riding on streets with bike lanes has been known to fall from 44% pre-installation to 5% or less after.

    I’d suggest that the bike menace appears more dangerous because it’s relatively new, not because it is actually more dangerous. You’ve just grown used to accepting the deaths and injuries caused by drivers.

  • els

    you are correct. and therein lies the problem. the issue of bike pedestrian crashes is not being examined. Given that most such accidents are not reported and not necessarily life threatening I think there is a big potential issue here if only the powers that be would try to collect the data. Also there, IMHO, too much emphasis on mortality data and not injuries. From an actuarial standpoint, injuries cost more.

  • cc

    It would be interesting to hear more details about validity of the comparison inside and outside the bike share service area. Do CItiBikes not operate outside the service area? Was the service area defined as the furthest region within which any CItiBikes traveled or was it some arbitrary zone around stations or known popular routes? I’m not saying this part of the methodology was invalid, but if presence of CitiBikes results in an enormous number of accidents just outside the “service area,” they would not only be omitted from the in-service-area total, but they would be a significant factor further increasing the proportion of external accidents.

  • Would be great to have an option to scan each and every citibike – which would show who is using it at the time – as a tool for the generally aloof nypd, in case a biker is stopped. Since that’s not going to happen any time soon, nor will functioning bike-level cameras be built at random intersections, how else can you hold the bikers responsible?

    Bloomberg, you’re truly a masshole.