showing that the number of bike trips in Portland dropped 5 percent
huge caveat,
Annual automobile counts are not typically conducted on the four bridges. However, in 2009 PBOT did conduct counts on the four bicycle-friendly bridges. Those counts showed an overall ten percent decrease from 2005, when the last counts were taken on all but the Steel Bridge.
declined since around 2000.
it's not possible to say by how much car travel across bridges decreased