Subways, Strikes, and Slowdowns: The Impacts of Public Transit on Traffic Congestion, NBER Working Paper, February 2013

Below is the abstract from a NBER Working Paper by Michael L. Anderson on the impacts of the cessation of public transit programs--typically by worker strikes and slowdowns.  Looking through this other end of the spyglass, the report highlights the disproportionate effect public transit has on reducing congestion--and the adverse consequences when it is not available.  

Here is Paul Krugman's short summary of the paper:  "(T)he author argues that mass transit has a significant impact in reducing traffic congestion, even when it carries only a small fraction of commuters. Why? Because commuters who take mass transit are, very disproportionately, people who would otherwise be driving on the most congested routes. So even the small number of people taken off the roads has a surprisingly large effect in reducing travel delays."

The paper is available from NBER for $5.00 to members (free) if you want to read the full text.  You can reach the webpage for the paper by clicking on the paper's title below.    

 Subways, Strikes, and Slowdowns: The Impacts of Public Transit on Traffic Congestion

Michael L. Anderson

NBER Working Paper No. 18757
Issued in February 2013
NBER Program(s):   EEE   PE

Public transit accounts for only 1% of U.S. passenger miles traveled but nevertheless attracts strong public support. Using a simple choice model, we predict that transit riders are likely to be individuals who commute along routes with the most severe roadway delays. These individuals’ choices thus have very high marginal impacts on congestion. We test this prediction with data from a sudden strike in 2003 by Los Angeles transit workers. Estimating a regression discontinuity design, we find that average highway delay increases 47% when transit service ceases. This effect is consistent with our model’s predictions and many times larger than earlier estimates, which have generally concluded that public transit provides minimal congestion relief. We find that the net benefits of transit systems appear to be much larger than previously believed.  (Emphasis added)