-57.14% is the change from 931 to 399
Calculation steps:
[( 399 - 931 ) ÷ 931] x 100 = -57.14%
Formula
Percentage change = [(399 - 931) / 931] x 100
Subtract the new number by the original number
399 - 931 = -532
-532 ÷ 931 = -0.5714285714285714
-0.5714285714285714 x 100 = -57.14%