-96.16% is the change from 391 to 15
Calculation steps:
[( 15 - 391 ) ÷ 391] x 100 = -96.16%
Formula
Percentage change = [(15 - 391) / 391] x 100
Subtract the new number by the original number
15 - 391 = -376
-376 ÷ 391 = -0.9616368286445013
-0.9616368286445013 x 100 = -96.16%