-89.71% is the change from 680 to 70
Calculation steps:
[( 70 - 680 ) ÷ 680] x 100 = -89.71%
Formula
Percentage change = [(70 - 680) / 680] x 100
Subtract the new number by the original number
70 - 680 = -610
-610 ÷ 680 = -0.8970588235294118
-0.8970588235294118 x 100 = -89.71%