-57.19% is the change from 320 to 137
Calculation steps:
[( 137 - 320 ) ÷ 320] x 100 = -57.19%
Formula
Percentage change = [(137 - 320) / 320] x 100
Subtract the new number by the original number
137 - 320 = -183
-183 ÷ 320 = -0.571875
-0.571875 x 100 = -57.19%