Historically, general funds have been used for road needs, and local governments continue to raise the bulk of their local source funding from general funds. One advantage of such funding is the increased legislative scrutiny and prioritization of needs that results. Any increase in spending on transportation requires an offsetting cut in other expenditures that are not deemed as important unless general taxes are to be increased. However, if transportation is as critical a function of government as some believe, there may be merit in taxing the users of the system so as to assure a dedicated source of funds for investment on a regular basis. Users have generally expressed a willingness to pay taxes for roads, if they could be assured that the funds would indeed be invested in the road system. General fund appropriations do not provide this dedicated source of funds which users and taxpayers know will be spent on the roads. The other disadvantage of general fund appropriations is the potential for annual fluctuations in the level of funding. This can create problems in an environment where projects may take up to seven or eight years to complete.