Democrats have tried to make political hay out of the growth in income inequality over the last 35 years.

But here's a statistical shocker from economist Douglas Holtz-Eakin of the American Action Forum. Income inequality became more extreme under Presidents Obama and Clinton than under the Bushes. That's according to Census Bureau data known as the Gini coefficient, one of the most prominent gauges of income inequality.

"How does this happen?" Holtz-Eakin writes on his group's web site. "The economic lifeblood of the middle class is labor earnings and the central tenet of raising middle-class income is increases in (inflation-adjusted) earnings."

But by this measure Obama and Clinton beat only President George H.W. Bush, while President George W. Bush bests all three.

"This straight reading of the record raises the fundamental question: if the core of progressive policies did not succeed in raising wages and lowering inequality for the past six years, why should the voters have any interest in suffering for another four to eight?" Holtz-Eakin says.

Median household income fell to $54,600 in April from $56,207 in December 2007, when the last recession began, according to inflation-adjusted estimates from Sentier Research. That income decline occurred even as the labor market shows signs of healing with the unemployment rate falling to 5.6 percent in May from a peak of 10 percent in October 2009.

Freelance Living

Elsewhere on the personal income front, more and more of us are working as freelancers, and that translates into more and more of us worrying about job security.

The number of job categories populated mostly by independent contractors soared to 32 million, or 18 percent of all jobs, in 2014 from 20 million in 2001, according to Economic Modeling Specialists, a labor research firm, The New York Times reports.

As for the increased worry, a Gallup poll last year showed that 23 percent of Americans were concerned that their work hours would be pared up from the low to mid-teens percent in the years before the 2007-09 recession.

“In the past, firms overstaffed and offered workers stable hours,” Susan Houseman, a labor economist at the Upjohn Institute for Employment Research, told The Times. “All of these new staffing models mean shifting risk onto workers, making work less secure.”

The upshot of all this is a “transformation that promises new efficiencies and greater flexibility for ‘employers’ and ‘employees’ alike, but which threatens to undermine the very foundation upon which middle-class America was built,” venture capitalist Nick Hanauer and labor leader David Rolf write in Democracy Journal.

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