(Northbrook, IL)  --  A new study released by Allstate Insurance ranks Portland among the U.S. cities with the worst drivers.  The annual America's Best Drivers Report ranks Portland at 177th out of 200, down from 154th in 2013.  According to the study, Portland drivers average seven-point-three years between crashes, compared to the national average of ten years.  Seattle comes in at 173rd, while Fort Collins, Colorado ranks as the city with the nation's safest drivers.