-94.63% is the change from 391 to 21
Calculation steps:
[( 21 - 391 ) ÷ 391] x 100 = -94.63%
Formula
Percentage change = [(21 - 391) / 391] x 100
Subtract the new number by the original number
21 - 391 = -370
-370 ÷ 391 = -0.9462915601023018
-0.9462915601023018 x 100 = -94.63%