Pamplovia raised its estate tax rate from 30% to 50%. However, it grandfathered in families whose householders

Question:

Pamplovia raised its estate tax rate from 30% to 50%. However, it “grandfathered” in families whose householders were over 80 years old, allowing these families to be assessed the original 30% estate tax. How could you go about estimating the effects of estate tax rates in Pamplovia on the magnitude of bequests.