-50.31% is the change from 805 to 400
Calculation steps:
[( 400 - 805 ) ÷ 805] x 100 = -50.31%
Formula
Percentage change = [(400 - 805) / 805] x 100
Subtract the new number by the original number
400 - 805 = -405
-405 ÷ 805 = -0.5031055900621118
-0.5031055900621118 x 100 = -50.31%