-54.29% is the change from 921 to 421
Calculation steps:
[( 421 - 921 ) ÷ 921] x 100 = -54.29%
Formula
Percentage change = [(421 - 921) / 921] x 100
Subtract the new number by the original number
421 - 921 = -500
-500 ÷ 921 = -0.5428881650380022
-0.5428881650380022 x 100 = -54.29%