The super rich got super richer as the gap between them and the rest of Americans continued to widen over the last few years, according to a new Federal Reserve report.

In its Study of Consumer Finances, released every three years, the Fed found that the wealthiest 3% of American households controlled 54.4% of the nation's wealth in 2013, a slight increase from its last survey in 2010. It's also substantially higher from the 44.8% they held in 1989, showing how quickly the income divide has been growing over the past decade or so.

At the same time, the share of wealth held by the bottom 90% fell to 24.7% in 2013. That's compared to 33.2% in 1989.

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"Data confirm that the shares of income and wealth held by affluent families are at modern historically high levels," the report said. "The gains in income and wealth shares have been concentrated among the top few percentiles."

The report also looked at Americans' earnings. While the median income of all Americans fell by 5% between 2010 and 2013, the mean income increased by 4%. That means gains by the wealthiest segment of the population pulled up the average.

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All of the income gains came from the wealthy, with the top 3% accounting for 30.5% of all income. The bottom of the scale continued to see their incomes shrink.