-93.9% is the change from 344 to 21
Calculation steps:
[( 21 - 344 ) ÷ 344] x 100 = -93.9%
Formula
Percentage change = [(21 - 344) / 344] x 100
Subtract the new number by the original number
21 - 344 = -323
-323 ÷ 344 = -0.938953488372093
-0.938953488372093 x 100 = -93.9%