-73.13% is the change from 320 to 86
Calculation steps:
[( 86 - 320 ) ÷ 320] x 100 = -73.13%
Formula
Percentage change = [(86 - 320) / 320] x 100
Subtract the new number by the original number
86 - 320 = -234
-234 ÷ 320 = -0.73125
-0.73125 x 100 = -73.13%