-89.15% is the change from 387 to 42
Calculation steps:
[( 42 - 387 ) ÷ 387] x 100 = -89.15%
Formula
Percentage change = [(42 - 387) / 387] x 100
Subtract the new number by the original number
42 - 387 = -345
-345 ÷ 387 = -0.8914728682170543
-0.8914728682170543 x 100 = -89.15%