Even if your system is super efficient, you still pay the flat rate.

即使您的系统超级节电，您还是需要付固定的费用。

youdao

The tax rate could very well be a flat tax system of say 20% gross income.

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But, best of all, Bulgaria has a flat tax system with a 10% income tax rate and a 10% corporate tax rate.

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Effective January 2013, Slovakia, with a 19% flat income tax system, raised its corporate tax rate to 23%, and introduced a second 25% tax bracket for higher personal incomes.

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