-86.27% is the change from 306 to 42
Calculation steps:
[( 42 - 306 ) ÷ 306] x 100 = -86.27%
Formula
Percentage change = [(42 - 306) / 306] x 100
Subtract the new number by the original number
42 - 306 = -264
-264 ÷ 306 = -0.8627450980392157
-0.8627450980392157 x 100 = -86.27%