-88% is the change from 850 to 102
Calculation steps:
[( 102 - 850 ) ÷ 850] x 100 = -88%
Formula
Percentage change = [(102 - 850) / 850] x 100
Subtract the new number by the original number
102 - 850 = -748
-748 ÷ 850 = -0.88
-0.88 x 100 = -88%
Example