-84.78% is the change from 670 to 102
Calculation steps:
[( 102 - 670 ) ÷ 670] x 100 = -84.78%
Formula
Percentage change = [(102 - 670) / 670] x 100
Subtract the new number by the original number
102 - 670 = -568
-568 ÷ 670 = -0.8477611940298507
-0.8477611940298507 x 100 = -84.78%