-51.79% is the change from 811 to 391
Calculation steps:
[( 391 - 811 ) ÷ 811] x 100 = -51.79%
Formula
Percentage change = [(391 - 811) / 811] x 100
Subtract the new number by the original number
391 - 811 = -420
-420 ÷ 811 = -0.5178791615289766
-0.5178791615289766 x 100 = -51.79%