The total market value of real estate in Altonville has steadily declined over the past four years. This decline has meant that the overall figure on which the city' s property tax is based - the assessed value of that real estate - has also declined. Moreover, the percentage of assessed value that was paid as property taxes to the city did not change during this period. The information above most strongly supports which of the following? ['During the past four years, Altonville officials also did not increase tax rates on other sources of revenue such as retail sales or business profits.', "The percentage of Altonville's overall revenue that was collected from property taxes did not change over the past four years.", 'The total amount of revenue that Altonville has collected from property taxes has declined over the past four years.', 'Altonville officials had proposed raising property tax rates during the past four years but never did so because of strong opposition from property owners.']