-95.09% is the change from 815 to 40
Calculation steps:
[( 40 - 815 ) ÷ 815] x 100 = -95.09%
Formula
Percentage change = [(40 - 815) / 815] x 100
Subtract the new number by the original number
40 - 815 = -775
-775 ÷ 815 = -0.950920245398773
-0.950920245398773 x 100 = -95.09%