-64.29% is the change from 420 to 150
Calculation steps:
[( 150 - 420 ) ÷ 420] x 100 = -64.29%
Formula
Percentage change = [(150 - 420) / 420] x 100
Subtract the new number by the original number
150 - 420 = -270
-270 ÷ 420 = -0.6428571428571429
-0.6428571428571429 x 100 = -64.29%