Who's Divvying in the winter?

April 2, 2015

divvy bikes in Chicago's snowy winter

Photo by Chicago Suntimes

For the second year in a row, Divvy recently put out a challenge to scientists, designers, students, civic minds, planners, and programmers to analyze and present a year’s worth of ride data in visually compelling ways. They opened up their data for the 2.45 million rides that occurred in 2014. As an avid Divvy rider, I was very excited to take a look at the data and participate in the challenge.

Divvy & Chicago Weather

Even though I prefer to commute via Divvy over public transportation, I only use Divvy regularly from April to November because I can't handle Chicago’s cold—and long—winter. Since weather is the deciding factor as to whether or not I use Divvy, for the Divvy Data Challenge I wanted to find out how many other people felt the same way. Some of the questions I wanted to answer were:

  • “How much does weather affect Divvy rides?”
  • “Do trips change on cold days?”
  • “Are there really people riding on Chicago’s most unbearably cold days?”
To do this I created an interactive dashboard that allows viewers to see how Chicago’s weather affected Divvy rides in 2014. I chose to compare number of rides, average time per ride, and average distance per ride to the average temperature over the course of the year. I also created a bar chart to compare ride count on the coldest and hottest days of 2014. The viewer can filter all charts by customer type or gender. Here are some of the insights I discovered.

Number of Rides vs. Average Temperature

chart of divvy rides by distance

  • Temperature and ride count curves have very similar shapes.
    As temperature increases and decreases throughout the year, so do the number of rides. In the summer and fall especially, temperature and ride count seem to be highly correlated. You can see that the abnormally warm days in mid-September and mid-October result in ride count spikes as well.
  • Among subscribers, there are more male rides than female rides.
    This chart makes it clear that there are more male than female subscribers riding throughout the year. 75% of all subscriber rides were by men.
  • One-time customers ride in the summer.
    The majority of customer rides take place from May - September. The most customer rides, 12,092, occurred on May 25, 2014, which was Memorial Day weekend.

Average Time per Ride

chart of divvy rides by distance

  • Female rides are longer than male rides.
    Based on the ride data we have, female rides are about 2.5 minutes longer on average than males. If we had a larger sample of female rides, this gap between males and females might be smaller.
  • One-time customer rides are much longer than subscriber rides.
    The average customer ride time is 27.9 minutes and the average subscriber ride time is 11.9 minutes.
  • Average minutes per ride is impacted more by customer type than by temperature.
    The average minutes per ride for subscribers and one-time customers is pretty steady throughout the year, no matter how warm or cold it is. Rides are shorter in colder temperatures overall because the mix of customer type changes (i.e., fewer tourists) in the winter.

Average Distance per Ride

chart of divvy rides by distance

  • Average miles per ride is impacted by weather.
    Even though the average miles per ride only varies between 0.9 miles and 1.3 miles, it is clear by looking at the curve of the blue line vs the gray line in this chart that the rise and drop of temperature has an impact on the rise and drop of distance traveled throughout the year.
  • As predicted by average minutes per ride, females ride slightly farther than males. But one-time customers don’t ride much farther than subscribers.
    Customers ride 16 minutes longer than subscribers on average, but they only travel 0.1 miles farther. This is likely because tourists take scenic routes or start and end at the same station more often than commuters.

2014’s Hottest & Coldest Days

Coldest Divvy days in 2014 Hottest Divvy days in 2014

  • There were 451 rides on Divvy’s coldest day in 2014 at -4 degrees.
    The temperature on January 28th was an average of -4 degrees. The 451 rides were split up between 443 subscriber rides (403 male / 40 female) and 8 one-time customers.
  • One-time customers ride when it’s warm, not when it’s cold.
    This chart makes the drastic change in customer behavior between warm and cold days apparent. Only 3% of rides were made by customers on the 30 coldest days whereas 44% of rides were made by customers on the 30 warmest days.

Divvy Members are impressive.

I mentioned that I wanted to see how weather impacts Divvy rides overall since it greatly impacts how much I ride. It’s clear that temperature does affect Divvy ridership, but not for everyone. I’m very impressed with the hundreds of Chicagoans who ride every day, no matter how cold it is. #DivvyOn, Chicago!

contributors to this post

headshot of Laura Rokita
Laura
headshot of Brian Lange
Brian