-42.19% is the change from 320 to 185
Calculation steps:
[( 185 - 320 ) ÷ 320] x 100 = -42.19%
Formula
Percentage change = [(185 - 320) / 320] x 100
Subtract the new number by the original number
185 - 320 = -135
-135 ÷ 320 = -0.421875
-0.421875 x 100 = -42.19%