Over 20 years, the repeal would cost $982 billion in lost revenues.

Permanent Repeal Of The Estate Tax Would Be Costly, Yet Would Benefit Only A Few, Very Large Estates, 6/17/03

According to Joint Committee on Taxation estimates, this measure would cost $162 billion through 2013.

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Over the subsequent decade, 2014 through 2023, permanent repeal would lose approximately $820 billion in revenues. More than $460 billion of this revenue loss could be averted by retaining the estate tax with a $3.5 million exemption and a top rate of 45 percent.