-96.18% is the change from 393 to 15
Calculation steps:
[( 15 - 393 ) ÷ 393] x 100 = -96.18%
Formula
Percentage change = [(15 - 393) / 393] x 100
Subtract the new number by the original number
15 - 393 = -378
-378 ÷ 393 = -0.9618320610687023
-0.9618320610687023 x 100 = -96.18%