That beloved mortgage deduction skews to the wealthy

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The vast majority of people see no tax benefit from the deduction, because just 20 percent of filers use it, according to the Urban-Brookings Tax Policy Center. And if Republicans successfully deliver generous increases in the standard deduction while eliminating other deductions, its utility could decline even more.

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In an analysis of the GOP tax plan released last year, the Tax Policy Center estimated that of the 45 million filers who itemize, 38 million, or 84 percent, would opt for the $24,000 standard deduction proposed under the Republican plan because it would exceed the combined value of other deductions available to them.