Graph: Growth in Bicycle Commuting, 2000 – 2010
Last week, we shared with you the 2010 US Census Bureau American Community Survey bicycle commuting data. Here is a visual representation of the trends:
Thanks to Kate Powlison at Bikes Belong for putting together this very attractive graph using ACS data to show the growth of bike commuting since 2000 in the largest Bicycle Friendly Communities, non-BFCs, and the national rate. Click on the image for a larger version.
Another version here, without the 70 city average:
2010 Bike Commuter Statistics for 375 cities (all cities over 65,000 population that had bike commuter estimates)
The notes on the American Community Survey are worth repeating:
ACS limitations, notes, and cautions
- The ACS asks only about commuting. It does not tell us about bicycling for non-work purposes.
- Results are based on a survey of a sample of the population. Surveys take place throughout the year. The journey to work question asks respondents about the previous week.
- The journey to work question asks about the primary mode of transportation to work. The wording of the question undercounts the actual amount of bike commuting that occurs. It does not count people who rode once or twice a week or people who bike to transit (if the transit leg is longer than the bike leg).
- Since the ACS is a survey of a sample, the results are estimates. The ACS releases a margin of error along with the estimate. Users can add and subtract the margin of error value from the estimate to find the top and bottom of the range within which the ACS is 90 percent confident in their estimate lies. Refer to the2010 city table for margins of error.
- Changes among years may not be statistically significant. Be cautious when drawing conclusions based on one year changes. Look at the trend over a number of years.
- The numbers reported here are for the “principal city,” not the larger Metropolitan Statistical Area (MSA).
- UPDATE: A note of caution from the US Census Bureau: ”The 2009 ACS and 2010 ACS 1-year estimates use different Census base years for the population estimates used in the ACS weighting. Estimates of population size are not comparable between 2009 and 2010. Estimates of percent distributions, rates, and ratios should be compared with caution. For more details, visit the ACS Research Note Change in Population Controls [PDF 366K].” The Bureau is urging users to use caution in interpreting the results, but not suggesting that users avoid comparisons all together.
- For detailed questions about methodology, contact the American Community Survey Office at 301-763-9810.