A new congressional study has found the incomes for the wealthiest one percent of Americans nearly tripled over the last three decades, far outpacing income growth for all other groups. Between 1979 and 2007, the average real after-tax household income grew by 275 percent for the wealthiest Americans. Income grew by just 40 percent for middle-class Americans during the same period. The study also found the wealthiest 20 percent of Americans made more money in 2007 than the rest of the country combined. Democratic Rep. Sandy Levin of Michigan said the report was “the latest evidence of the alarming rise in income inequality.”