More generally, the report says tax systems should not differentiate between income earned in different ways—between working for someone else, say, and self-employment.

该报告指出，一般说来，税收系统不应对收入方式不同的群体区别对待，无论是为他人打工还是个体经营。

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Gov. Romney paid his full self-employment tax (FICA and Medicare) on his material business income.

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He runs his consulting business as a sole proprietorship paying self-employment tax on the whole profit.

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Trade or business income that hits your return will often be subject to self-employment tax.

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