-53.9% is the change from 911 to 420
Calculation steps:
[( 420 - 911 ) ÷ 911] x 100 = -53.9%
Formula
Percentage change = [(420 - 911) / 911] x 100
Subtract the new number by the original number
420 - 911 = -491
-491 ÷ 911 = -0.5389681668496158
-0.5389681668496158 x 100 = -53.9%