-21.87% is the change from 855 to 668
Calculation steps:
[( 668 - 855 ) ÷ 855] x 100 = -21.87%
Formula
Percentage change = [(668 - 855) / 855] x 100
Subtract the new number by the original number
668 - 855 = -187
-187 ÷ 855 = -0.21871345029239767
-0.21871345029239767 x 100 = -21.87%