Graduation Year


Document Type




Degree Name

MS in Civil Engineering (M.S.C.E.)

Degree Granting Department

Civil and Environmental Engineering

Major Professor

Robert Bertini, Ph.D.

Committee Member

Steven Polzin, Ph.D.

Committee Member

Pei-Sung Lin, Ph.D.

Committee Member

Fred Mannering, Ph.D.


Aging Population, Gasoline Prices, Geographic Distribution, Growth in Telecommuting, Vehicle Availability


Public transit, an important mobility service for many, has incurred ridership decline in the U.S. for the past three years. In 2014, U.S. transit ridership was 10.74 billion unlinked passenger trips. In 2015, total ridership was 1.0 percent fewer, and the 2016 decrease was 2.2 percent from 2015. The consistent abandonment of transit in the U.S. does not seem to be ending. In 2017, ridership predicted from year-to-date data is 2.4 percent less than 2016. Furthermore, per capita ridership has decreased 17 percent since 1980. Both the short-term ridership trend and long-term per capita ridership trend is concerning given the increased spending and service provision during the same periods.

In seeking to understand the many factors that influence transit ridership trends, it is important to analyze each so that policymakers and practitioners can respond and position transit accordingly. Numerous demographic and economic phenomena help explain this decline in transit use. This research focuses on five of these considerations – age, vehicle availability, telecommuting, fuel price, and geographical distribution of the population.