Deposits collected by a taxpayer on packaging materials leased or lent out in the sales of goods and that are recorded and accounted for separately are not included in the sales amount for tax levy.

纳税人为销售货物而出租出借包装物收取的押金，单独记帐核算的，不并入销售额征税。

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It is possible for tax rates to be so high that raising them further would in fact decrease the amount of revenue collected, not increase it.

FORBES: There Really is a Laffer Curve