-87.01% is the change from 770 to 100
Calculation steps:
[( 100 - 770 ) ÷ 770] x 100 = -87.01%
Formula
Percentage change = [(100 - 770) / 770] x 100
Subtract the new number by the original number
100 - 770 = -670
-670 ÷ 770 = -0.8701298701298701
-0.8701298701298701 x 100 = -87.01%