-94.62% is the change from 390 to 21
Calculation steps:
[( 21 - 390 ) ÷ 390] x 100 = -94.62%
Formula
Percentage change = [(21 - 390) / 390] x 100
Subtract the new number by the original number
21 - 390 = -369
-369 ÷ 390 = -0.9461538461538461
-0.9461538461538461 x 100 = -94.62%