To help families, I'll triple the personal deduction for children and eliminate the marriage tax penalty.

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However, single filers retained the full personal exemption and standard deduction, unlike married filers.

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Over the years, the personal exemption and standard deduction have not kept pace with inflation, so today 70% of the population is subject to income taxes.

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That is the point at which gross income begins to exceed the standard deduction and the deduction for the personal exemption.

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In 1960 only 15% of federal income tax returns had a zero tax liability, due mostly to low taxable income, a standard deduction, the personal exemption, the dependent exemption, and the Earned Income Tax Credit (a direct subsidy to people for being poor).

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But what emerged was a clear improvement of the tax code, with a top statutory personal income rate of 28 percent and the doubling of the standard deduction.

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Taxpayers must figure the percentage of business versus personal use and apply the business percentage to total expenses to arrive at the deduction.

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If you make a personal nonbusiness loan and you are unable to collect the amount, you may be able to claim a deduction for the amount for the year that the debt becomes completely worthless.

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Personal legal expenses aren't deductible but those related to one's job can be claimed as a miscellaneous deduction.

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