-48.84% is the change from 821 to 420
Calculation steps:
[( 420 - 821 ) ÷ 821] x 100 = -48.84%
Formula
Percentage change = [(420 - 821) / 821] x 100
Subtract the new number by the original number
420 - 821 = -401
-401 ÷ 821 = -0.4884287454323995
-0.4884287454323995 x 100 = -48.84%