-94.38% is the change from 320 to 18
Calculation steps:
[( 18 - 320 ) ÷ 320] x 100 = -94.38%
Formula
Percentage change = [(18 - 320) / 320] x 100
Subtract the new number by the original number
18 - 320 = -302
-302 ÷ 320 = -0.94375
-0.94375 x 100 = -94.38%