-18.36% is the change from 550 to 449
Calculation steps:
[( 449 - 550 ) ÷ 550] x 100 = -18.36%
Formula
Percentage change = [(449 - 550) / 550] x 100
Subtract the new number by the original number
449 - 550 = -101
-101 ÷ 550 = -0.18363636363636363
-0.18363636363636363 x 100 = -18.36%