-0.24% is the change from 420 to 419
Calculation steps:
[( 419 - 420 ) ÷ 420] x 100 = -0.24%
Formula
Percentage change = [(419 - 420) / 420] x 100
Subtract the new number by the original number
419 - 420 = -1
-1 ÷ 420 = -0.002380952380952381
-0.002380952380952381 x 100 = -0.24%