-62.5% is the change from 320 to 120
Calculation steps:
[( 120 - 320 ) ÷ 320] x 100 = -62.5%
Formula
Percentage change = [(120 - 320) / 320] x 100
Subtract the new number by the original number
120 - 320 = -200
-200 ÷ 320 = -0.625
-0.625 x 100 = -62.5%