-1.09% is the change from 549 to 543
Calculation steps:
[( 543 - 549 ) ÷ 549] x 100 = -1.09%
Formula
Percentage change = [(543 - 549) / 549] x 100
Subtract the new number by the original number
543 - 549 = -6
-6 ÷ 549 = -0.01092896174863388
-0.01092896174863388 x 100 = -1.09%