Statutory rates were too high, and deductions and exemptions too many, to make either tax collections efficient or economic activity optimal.

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That can potentially open a can of worms, because if the tax deductions are reduced for corporations and not for small businesses, then many savvy corporations could either break off into small units, or relocate where taxes are lower if changes to the statutory rate do not make up for the loss from closing the tax deductions.

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American multinationals like Apple are charged the statutory 35% rate when they file Form 1120 with the IRS. But their effective tax rate after credits and deductions is closer to 28% currently, according to BDO.

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