Initiated constitutional amendment signature requirements as percentage of registered voters

The map shows the number of signatures required to qualify an initiated constitutional amendment for the ballot in each state expressed as a percentage of registered voters in the state.

The exact number of signatures required for ballot initiatives vary by state and by type of measure. The exact number required, according to the state's constitution or state law, is tied to another number, such as the number of votes cast in a recent election.
Chart: BallotpediaSource: Ballotpedia