http://demographia.blogspot.com/2008/05/paris-light-rail-tram-increases.html
According to University of Paris researchers, the new (2007) Paris
tramway (light rail or streetcar) along the south boulevards des
Marechaux has attracted, at most, 3 percent of its ridership from
cars. This finding is made in a paper entitled Paris: un tramway
nomme desir (Paris: A Streetcar Named Desire), published in August
2007 by Remy Prud'homme, Martin Koenig, Pierre Kopp. The authors note
that this small modal shift "once again shows the limits of modal
shift strategies" (our liberal interpretation of the French).
While traffic along the boulevard has been reduced, this has been
accomplished by narrowing the capacity and forcing traffic to
parallel roadways. The result has been to increase traffic congestion
and, as occurs when traffic becomes slower and more erratic, increase
fuel consumption, which of course leads to higher greenhouse gas
emissions. It is estimated the tramway has resulted in a net increase
of nearly 40,000 tonnes of CO2 annually.
