Economically efficient prices for the passenger transportation system in the Greater Cairo Metropolitan Area would account for broader societal costs of traffic congestion and accidents, and local and global pollution. A .20 per gallon gasoline tax (2006 US would be economically efficient, compared with the current subsidy of .20 per gallon. Removal of the existing subsidy alone would achieve about three-quarters of the net benefits from subsidy elimination and the tax. Per-mile tolls could target congestion and accident externalities more efficiently than fuel taxes, although they are not practical at present. A combination of .80 per gallon gasoline tax to address pollution (versus .20 without tolls), and .12 and .19 tolls per vehicle mile on automobiles and microbuses, respectively, to address traffic congestion and accident externalities (versus .22 without fuel taxes) would be most efficient. Current public bus and rail subsidies are relatively close to efficient levels in the absence of such policies
however, if automobile and microbus externalities were fully addressed through more efficient pricing, optimal subsides to public transit would be smaller than current levels.