Another suggestion is to make the map of states that makes staying on
the right lane compulsory unless overtaking the slower vehicle. Colorado
legislated the law last year, and I've noticed the dramatic improvement
in lane discipline and use a year after. Perhaps some statistics to
reflect the reduction of accidents and such?

California is so bad! So many motorists clutter up the left lanes,
forcing me to overtake them on the right lane and pray that no vehicles
are entering the highway as I overtake them!

John F. Carr schrieb:
> With three states raising speed limits this year I decided
> to make a map of where America stands:
> http://www.mit.edu/~jfc/speed/states.gif
>
> The map shows the highest speeds posted in the state; in
> the case of Texas I anticipated the posting of 80 MPH speed
> limits later this year.
>
> The corresponding map for two lane roads is
> http://www.mit.edu/~jfc/speed/states%202L.gif
>
> States with some sort of rumbling about increases in recent
> years include Idaho (75 two lane), Kansas (75), Kentucky
> (60 two lane, 70 freeway), Oregon (70), Minnesota (60 two
> lane and 75 Interstate), and Wisconsin (75 freeway). All
> of these states have neighbors with higher speed limits.
>
> I wanted to make a map for four lane roads but I don't think
> it would be very informative. In some states rural divided
> highways are almost entirely freeways; in others they are
> limited access without interchanges; in others they are not
> limited access.
>
> States where I know there are non-freeway rural four lane roads
> with the maximum speed limit on such roads between two lane
> freeway limits are Alabama (65 on four lane roads), Florida
> (65 on divided highways), Indiana (60 on divided highways
> without access control), Missouri (65 on divided highways
> without access control), North Dakota (70 on divided highways),
> South Dakota (70 on divided highways), Washington (65 on
> divided highways), and West Virginia (65 on limited access
> corridor routes). Of the rest, some post expressways like
> freeways and others post expressways like two lane roads.