-1.61% is the change from 558 to 549
Calculation steps:
[( 549 - 558 ) ÷ 558] x 100 = -1.61%
Formula
Percentage change = [(549 - 558) / 558] x 100
Subtract the new number by the original number
549 - 558 = -9
-9 ÷ 558 = -0.016129032258064516
-0.016129032258064516 x 100 = -1.61%