Evidence to Inform a Cycling and Walking Investment Strategy
BACKGROUND
In the United States, one out of ten students travel to school using physically active modes of transportation like bicycling (1.1%) and walking (9.6%), and among U.S. workers, one in 25 commutes to their job on foot (2.9%) or bicycle (1.1%).1 Increasing the use of physically active transportation may be a cost-effective and sustainable strategy to increase population physical activity and improve health2,3 when compared to car travel.

PURPOSE
Researchers used a difference-in-difference analytical strategy to calculate the absolute difference over time in the percentage point change in the proportion of commuters getting to work via a bicycle or by walking in counties with “high investment” in funding that supports bike and pedestrian facilities compared to the difference over time in similar counties with “low investment” in these resources.

METHODS
Researchers used 2000 U.S. Census Bureau and the five-year 2016 American Community Survey data on the transportation mode that workers in counties with a population over 100,000 regularly reported using to get to and from work in the past week. Physically active modes included bicycling and walking. Researchers summarized county-level data from the Fiscal Management Information System (FMIS) of the Federal Highway Administration (FHWA)4 on federal funding obligated annually overall and for bicycle and pedestrian uses for fiscal years (FY) 1992 through 2015. “High investment counties,” counties at or above the 90th percentile for per capita federal funding were compared to similar “low investment” counties with per capita investments lower than the median level (i.e., 50th percentile). Researchers identified matched comparison communities among counties with similar baseline commuting rates, population size, density, metropolitan status, and county demographics, car ownership, and prior investment in bicycle and pedestrian infrastructure and programs.5 Comparisons between intervention and comparison counties were estimated using linear regression models accounting for matched pair indicators.

RESULTS
Only 2% of total transportation funding is dedicated to programs that support bike and pedestrian projects or infrastructure, but this varies by location. In high investment counties, 5.3% of all federal transportation funding is invested in biking and pedestrian infrastructure compared with just over 1% in low investment counties. High investment counties averaged just over $9 per person in walking and biking infrastructure compared with low investment counties that averaged about $1.50 per person. The share of commuters who biked to work increased significantly more between 2000 and 2016 in those counties that invested more in projects to support walking and biking than in similar counties that did not invest as much. The difference-in-difference analysis comparing high investment counties with state-matched low investment counties suggests that high investment in bicycle and pedestrian funding was associated with an increase of 0.33 (95% CI 0.16, 0.49, p<0.001) in the mode share of commuters traveling to work by bicycle.

CONCLUSION
Many communities may not invest sufficiently to support growth in biking and walking for transportation, recreation or exercise. Federal funding for bike and pedestrian projects can play a role in increasing the proportion of workers using a bike to get to and from work.

Presenter: Angie Cradock
Agency Affiliation: Harvard TH Chan School of Public Health

Presenter Biographical Statement: [biography]