-27.55% is the change from 421 to 305
Calculation steps:
[( 305 - 421 ) ÷ 421] x 100 = -27.55%
Formula
Percentage change = [(305 - 421) / 421] x 100
Subtract the new number by the original number
305 - 421 = -116
-116 ÷ 421 = -0.2755344418052256
-0.2755344418052256 x 100 = -27.55%