-83.61% is the change from 549 to 90
Calculation steps:
[( 90 - 549 ) ÷ 549] x 100 = -83.61%
Formula
Percentage change = [(90 - 549) / 549] x 100
Subtract the new number by the original number
90 - 549 = -459
-459 ÷ 549 = -0.8360655737704918
-0.8360655737704918 x 100 = -83.61%