-8.55% is the change from 550 to 503
Calculation steps:
[( 503 - 550 ) ÷ 550] x 100 = -8.55%
Formula
Percentage change = [(503 - 550) / 550] x 100
Subtract the new number by the original number
503 - 550 = -47
-47 ÷ 550 = -0.08545454545454545
-0.08545454545454545 x 100 = -8.55%