-51.15% is the change from 391 to 191
Calculation steps:
[( 191 - 391 ) ÷ 391] x 100 = -51.15%
Formula
Percentage change = [(191 - 391) / 391] x 100
Subtract the new number by the original number
191 - 391 = -200
-200 ÷ 391 = -0.5115089514066496
-0.5115089514066496 x 100 = -51.15%