So even if we’d raised the minimum wage to $15 an hour, the top 10 percent would still have emerged from the 2009-2014 period with a substantially larger share of the increase in the nation’s income than the bottom 90 percent. Inequality would still have increased, just not by as much. (I assume here that raising the minimum wage would not have reduced the income of those in the top 10 percent.)

Of course, policy makers have more options for reducing inequality than simply lifting up the working poor. Though raising pay for middle-income workers is much more complicated than raising the minimum wage, it’s certainly a reasonable aspiration for a politician concerned about inequality. Hillary Rodham Clinton, who said in her recent campaign kickoff speech that “we can’t stand by while inequality increases,” seemed to endorse this approach when she also said, “The middle class needs more growth and more fairness.”

But even raising middle-class wages probably wouldn’t be enough to offset the recent gains at the top. Since 1970, the best five-year run of income growth for the bottom 90 percent of families came between 1994 and 1999, when the group’s income rose by 14.1 percent, adjusting for population growth. If the bottom 90 percent had enjoyed the same run of income gains between 2009 and 2014, they would have collectively earned $683 billion during that time — almost identical to the $682 billion that the top 10 percent pulled in. And that would have been with the best income growth in almost two generations. (The actual increase in income for the bottom 90 percent was $79 billion.)

That almost certainly overstates the effect of increasing income growth for the bottom 90 percent of families. As a practical matter, it’s highly unlikely that you could increase income growth for the bottom 90 percent without also lifting income growth for those at the top, thereby increasing inequality.

The 1990s, which Mrs. Clinton approvingly cited in her speech, are a useful data point in this regard. Between 1992, the last full year of George H.W. Bush’s presidency, and 2000, the last full year of Bill Clinton’s, the average income of families in the bottom 90 percent grew by a seemingly impressive 15.4 percent. But the average income of families in the top 10 percent grew by over 50 percent. (The average income of the top 1 percent nearly doubled.) Inequality between the bottom 90 percent and the top 10 percent increased substantially.

Or, put differently: The Clinton years had very impressive economic growth over all, some of which benefited families in the bottom 90 percent. But a majority of the growth benefited those in the top 10 percent, who took home nearly two-thirds of all the income gains as a group.