Four little numbers

The internet is congestible, as are most networks.  Most U.S. roads and highways are managed on a first come-first served basis.  We even call some of them freeways.  Call it "road neutrality". 

My colleagues and I play with data from the 1990 and 2001 national surveys (NHTS).  All you need to know are four numbers:  Proportion of all person-trips that were nonwork trips during the AM peak in 1990 (Mondays-Thursday only, 6am-9am): 55%; proportion of all trips that were nonwork during the PM peak in 1990 (Mondays-Thursdays only, 4pm-7pm): 75%.  Corresponding proportions in 2001: 62% and 76%.

Backing off from "neutrality" and rationing by, say, willingness-to-pay might shift some of these trips to less congested periods (others might disappear or be consolidated or use alternate modes). 

There is no end of moaning about road and highway traffic.  But the next time you find yourself in a serious conversation on the merits and demerits of "net neutrality", think about these four numbers.