-85% is the change from 680 to 102
Calculation steps:
[( 102 - 680 ) ÷ 680] x 100 = -85%
Formula
Percentage change = [(102 - 680) / 680] x 100
Subtract the new number by the original number
102 - 680 = -578
-578 ÷ 680 = -0.85
-0.85 x 100 = -85%
Example