Oregon is among a dwindling number of states that still impose an estate or inheritance tax, according to a study released Thursday by the Pew Charitable Trusts.

By 2018, the number of states with estate and/or inheritance taxes will decrease from 19 to 17. Delaware and New Jersey are the latest states to eliminate those taxes. That has been the trend since 2001 — when U.S. lawmakers ended the income tax credit for estate or inheritance tax payments, the study found. At that time, every state had an estate tax, inheritance tax or both.

Opponents argue the taxes drive wealthy residents out of state and penalize small businesses and family farms.

Oregon’s estate tax ranges from 10 percent for estates valued at $1.1 million to $1.5 million and 16 percent for those valued at $9.5 million or greater. Estates worth $1 million or less are exempt.

Republicans have garnered Democrat support in eliminating the taxes by including the change as part of a larger tax package, the Pew study concluded. In New Jersey, for example, the state passed a gas tax that far exceeded the revenue that came from estate taxes.