Illinois could have saved a cumulative $3.5 billion had AFSCME salaries simply grown at the rate of inflation since 2004.

Under the union’s complicated salary formulas, yearly government-worker raises are higher than the American Federation of State, County and Municipal Employees would lead Illinoisans to believe.

Gov. Bruce Rauner’s administration said Thursday it has reached tentative agreements with unions representing roughly 300 engineers and operators, plumbers, steamfitters and machinists.