Computation of tax (1) In general The tax imposed by section 2501 for each calendar year shall be an amount equal to the excess of— (A) a tentative tax, computed under paragraph (2), on the aggregate sum of the taxable gifts for such calendar year and for each of the preceding calendar periods, over (B) a tentative tax, computed under paragraph (2), on the aggregate sum of the taxable gifts for each of the preceding calendar periods. (2) Rate schedule If the amount with respect to which the tentative tax to be computed is: The tentative tax is: Not over $10,000 18% of such amount. Over $10,000 but not over $20,000 $1,800, plus 20% of the excess over $10,000. Over $20,000 but not over $40,000 $3,800, plus 22% of the excess over $20,000. Over $40,000 but not over $60,000 $8,200, plus 24% of the excess over $40,000. Over $60,000 but not over $80,000 $13,000, plus 26% of the excess over $60,000. Over $80,000 but not over $100,000 $18,200, plus 28% of the excess over $80,000. Over $100,000 but not over $150,000 $23,800, plus 30% of the excess over $100,000. Over $150,000 but not over $250,000 $38,800, plus 32% of the excess of $150,000. Over $250,000 but not over $500,000 $70,800, plus 34% of the excess over $250,000. Over $500,000 $155,800, plus 35% of the excess of $500,000. . (2) Lifetime gift exemption (A) In general Paragraph (1) of section 2505(a) of the Internal Revenue Code of 1986 is amended to read as follows: (1) the amount of the tentative tax which would be determined under the rate schedule set forth in section 2502(a)(2) if the amount with respect to which such tentative tax is to be computed were $5,000,000, reduced by . (B) Inflation adjustment Section 2505 of such Code is amended by adding at the end the following new subsection: (d) Inflation adjustment (1) In general In the case of any calendar year after 2011, the dollar amount in subsection (a)(1) shall be increased by an amount equal to— (A) such dollar amount, multiplied by (B) the cost-of-living adjustment determined under section 1(f)(3) for