COLUMBUS: Like many cities across Ohio, Middletown is being squeezed on all sides. The Butler County burg of 51,000 has seen its revenue slip as the poor economy saps income taxes, its largest revenue source. The money it gets from the state — some 15 percent of its budget — is in peril as state leaders look to balance their own budget. Amid all this, Middletown's labor costs continue to climb at the rate of 4 percent a year.