Just an item of interest ... I am about 4 months into a 1 year study with WA state to evaluate the comparison of tax at the fuel pump verses a tax based primarily on miles driven. I have a separate GPS tracker that sends data every time the ignition is turned on to some gizmo in the sky that compiles data from over 2000(?) vehicles recording and sending data to study. I get a readout link for every trip that shows all kinds of data, including most importantly, what the approximate fuel tax would be based upon my mileage (currently calculated at about 49.5mpg) verses what I would be taxed based upon miles driven. Currently, I would be paying more than twice as much for miles driven basis verses WA state's very high fuel tax. When I pointed this out to researchers, they noted that compared to the average WA state registered car, I would still be paying less because I am using far less fuel (stats to support this were included). However, that doesn't help me since this is my 2nd hybrid and I am on my 5th year of hybrid driving. I am out of the state about 1/2 the year and they know that and need to factor that into the algorithm since many cars with cross back and forth between OR/WA and ID/WA. I also urged them to include a vehicle-weight factor in their final algorithm so that the heavier cars will pay more to recognize that they cause more road damage. Of course, all electric vehicles will present an entirely different issue. This is just a study and would take legislative approval to implement.