-83.42% is the change from 549 to 91
Calculation steps:
[( 91 - 549 ) ÷ 549] x 100 = -83.42%
Formula
Percentage change = [(91 - 549) / 549] x 100
Subtract the new number by the original number
91 - 549 = -458
-458 ÷ 549 = -0.8342440801457195
-0.8342440801457195 x 100 = -83.42%