A newly formed eastern Iowa “think tank” has issued a report criticizing republican plans to eliminate the state tax on Social Security benefits. Elderly Iowans who earn 32-thousand dollars or more each year pay income taxes on those benefits. University of Iowa professor Peter Fisher says the cut is unfair because it shifts the tax burden from well-to-do elderly Iowans to younger workers.Fisher says 71 percent of Iowa retirees are already exempted from Social Security taxes, and it’s only upper-income seniors who have to pay the income tax on those benefits. Jamie Van Fossen, the republican from Davenport who leads the House Ways and Means Tax Committee, doesn’t buy the argument the tax break will shift Iowa’s tax burden from the elderly to the young. Van Fossen says the Social Security tax is one of the reasons rich, elderly Iowans move to other states. Professor Fisher says that’s hard to believe. Fisher is part of the new “Iowa Policy Project” — a new “think tank” of academics that plan to issue reports on issues under debate in Iowa. Fisher is an economist who teaches Urban and Regional Planning at the University of Iowa.