-15.95% is the change from 815 to 685
Calculation steps:
[( 685 - 815 ) ÷ 815] x 100 = -15.95%
Formula
Percentage change = [(685 - 815) / 815] x 100
Subtract the new number by the original number
685 - 815 = -130
-130 ÷ 815 = -0.15950920245398773
-0.15950920245398773 x 100 = -15.95%