-97.57% is the change from 617 to 15
Calculation steps:
[( 15 - 617 ) ÷ 617] x 100 = -97.57%
Formula
Percentage change = [(15 - 617) / 617] x 100
Subtract the new number by the original number
15 - 617 = -602
-602 ÷ 617 = -0.9756888168557536
-0.9756888168557536 x 100 = -97.57%