-50.8% is the change from 815 to 401
Calculation steps:
[( 401 - 815 ) ÷ 815] x 100 = -50.8%
Formula
Percentage change = [(401 - 815) / 815] x 100
Subtract the new number by the original number
401 - 815 = -414
-414 ÷ 815 = -0.5079754601226993
-0.5079754601226993 x 100 = -50.8%