§ 2010

A credit of the applicable credit amount shall be allowed to the estate of every decedent against the tax imposed by section
2001.

The amount of the credit allowable under subsection (a) shall be reduced by an amount equal to 20 percent of the aggregate amount allowed as a specific exemption under section
2521 (as in effect before its repeal by the Tax Reform Act of 1976) with respect to gifts made by the decedent after September 8, 1976.

For purposes of this section, the applicable credit amount is the amount of the tentative tax which would be determined under the rate schedule set forth in section
2001
(c) if the amount with respect to which such tentative tax is to be computed were the applicable exclusion amount determined in accordance with the following table:

The amount of the credit allowed by subsection (a) shall not exceed the amount of the tax imposed by section
2001.