-31.15% is the change from 610 to 420
Calculation steps:
[( 420 - 610 ) ÷ 610] x 100 = -31.15%
Formula
Percentage change = [(420 - 610) / 610] x 100
Subtract the new number by the original number
420 - 610 = -190
-190 ÷ 610 = -0.3114754098360656
-0.3114754098360656 x 100 = -31.15%