-40.24% is the change from 850 to 508
Calculation steps:
[( 508 - 850 ) ÷ 850] x 100 = -40.24%
Formula
Percentage change = [(508 - 850) / 850] x 100
Subtract the new number by the original number
508 - 850 = -342
-342 ÷ 850 = -0.4023529411764706
-0.4023529411764706 x 100 = -40.24%