This idea has been merged into another idea. To comment or vote on this idea, please visit RE7-I-4239 Pledges should be automatically marked as "Completed" when the last installment is committed and the balance is zero. Status Date would be the gift date of the installment payment..
I am not sure why this is not already a feature. The pledge should not remain "active" once you have received the final payment. This would benefit everyone who queries on pledge status.