-56.41% is the change from 390 to 170
Calculation steps:
[( 170 - 390 ) ÷ 390] x 100 = -56.41%
Formula
Percentage change = [(170 - 390) / 390] x 100
Subtract the new number by the original number
170 - 390 = -220
-220 ÷ 390 = -0.5641025641025641
-0.5641025641025641 x 100 = -56.41%