721—21.601 (43) Plan III supervisor district candidate signatures after a change in the number of supervisors. After the number of supervisors has been increased or decreased pursuant to Iowa Code section 331.203 or 331.204, the signatures for candidates at the next primary and general elections shall be calculated as follows:
	 21.601(1) Primary election. Divide the total number of votes cast in the county at the previous general election for the office of president or for governor, as applicable, by the number of supervisor districts and multiply the quotient by .02. If the result of the calculation is less than 100, the result shall be the minimum number of signatures required. If the result of the calculation is greater than or equal to 100, the minimum requirement shall be 100 signatures.
	 21.601(2) Nominations by petition. If the effective date of the change in the number of districts was later than the date specified in Iowa Code section 45.1(6), divide the total number of registered voters in the county on the date specified in Iowa Code section 45.1(6) by the number of supervisor districts and multiply the quotient by .01. If the result of the calculation is less than 150, the result shall be the minimum number of signatures required. If the result of the calculation is greater than or equal to 150, the minimum requirement shall be 150 signatures.