-32.1% is the change from 620 to 421
Calculation steps:
[( 421 - 620 ) ÷ 620] x 100 = -32.1%
Formula
Percentage change = [(421 - 620) / 620] x 100
Subtract the new number by the original number
421 - 620 = -199
-199 ÷ 620 = -0.3209677419354839
-0.3209677419354839 x 100 = -32.1%