Much of the city's tax base dissipated, leading to problems with funding education, sanitation, and traffic control within the city limits. In addition, residents in unincorporated suburbs had difficulty obtaining municipal services, such as sewage and building code enforcement. In 1958, a study recommended that the city of Jacksonville begin annexing outlying communities in order to create the needed tax base to improve services throughout the county. Voters outside the city limits rejected annexation plans in six referendums between 1960 and 1965.