-19.88% is the change from 488 to 391
Calculation steps:
[( 391 - 488 ) ÷ 488] x 100 = -19.88%
Formula
Percentage change = [(391 - 488) / 488] x 100
Subtract the new number by the original number
391 - 488 = -97
-97 ÷ 488 = -0.1987704918032787
-0.1987704918032787 x 100 = -19.88%