What Is Perimeter Target Rate?
Perimeter target rate is the percentage of a receiver's outside routes that ended with a pass thrown his way. Dividing by routes rather than snaps is what makes it a measure of trust rather than deployment: a receiver can lead the league in boundary snaps and still rank poorly here if the quarterback is not looking his way. Outside rates generally run below slot rates, because boundary routes take longer to develop and are thrown into tighter coverage, so compare a receiver to other perimeter players rather than across the two boards. Slot and perimeter rates are each computed against their own route total and are not two halves of one number.

