-66.42% is the change from 271 to 91
Calculation steps:
[( 91 - 271 ) ÷ 271] x 100 = -66.42%
Formula
Percentage change = [(91 - 271) / 271] x 100
Subtract the new number by the original number
91 - 271 = -180
-180 ÷ 271 = -0.6642066420664207
-0.6642066420664207 x 100 = -66.42%