90.91% is the change from 440 to 840
Calculation steps:
[( 840 - 440 ) ÷ 440] x 100 = 90.91%
Formula
Percentage change = [(840 - 440) / 440] x 100
Subtract the new number by the original number
840 - 440 = 400
400 ÷ 440 = 0.9090909090909091
0.9090909090909091 x 100 = 90.91%