-88.1% is the change from 420 to 50
Calculation steps:
[( 50 - 420 ) ÷ 420] x 100 = -88.1%
Formula
Percentage change = [(50 - 420) / 420] x 100
Subtract the new number by the original number
50 - 420 = -370
-370 ÷ 420 = -0.8809523809523809
-0.8809523809523809 x 100 = -88.1%