-96.5% is the change from 428 to 15
Calculation steps:
[( 15 - 428 ) ÷ 428] x 100 = -96.5%
Formula
Percentage change = [(15 - 428) / 428] x 100
Subtract the new number by the original number
15 - 428 = -413
-413 ÷ 428 = -0.9649532710280374
-0.9649532710280374 x 100 = -96.5%