-49.18% is the change from 305 to 155
Calculation steps:
[( 155 - 305 ) ÷ 305] x 100 = -49.18%
Formula
Percentage change = [(155 - 305) / 305] x 100
Subtract the new number by the original number
155 - 305 = -150
-150 ÷ 305 = -0.4918032786885246
-0.4918032786885246 x 100 = -49.18%