-5% is the change from 320 to 304
Calculation steps:
[( 304 - 320 ) ÷ 320] x 100 = -5%
Formula
Percentage change = [(304 - 320) / 320] x 100
Subtract the new number by the original number
304 - 320 = -16
-16 ÷ 320 = -0.05
-0.05 x 100 = -5%
Example