-10.63% is the change from 320 to 286
Calculation steps:
[( 286 - 320 ) ÷ 320] x 100 = -10.63%
Formula
Percentage change = [(286 - 320) / 320] x 100
Subtract the new number by the original number
286 - 320 = -34
-34 ÷ 320 = -0.10625
-0.10625 x 100 = -10.63%