well and badly maintained cars in a given model year. Thus, 20% of the early 1970's cars have lower emissions than the broken 1990's cars.

These results are illustrated for CO and HC in Figures 5 and 6. We believe these graphs can be used to show that a number of programs currently proposed or underway are not cost effective. These programs include alternative and reformulated fuels (which treat all cars as equal); scrappage programs that treat all old cars as gross polluters (which they are in the EPA computer model, but are not in reality); tighter new car standards that attempt to lower the already negligible emissions of well maintained new vehicles; and scheduled emission testing programs that also inconvenience all drivers in an attempt to influence the behavior of a few. Most of these points are amplified more quantitatively in the Policy Review section of the journal Science, May 19, 1995.