-3.68% is the change from 571 to 550
Calculation steps:
[( 550 - 571 ) ÷ 571] x 100 = -3.68%
Formula
Percentage change = [(550 - 571) / 571] x 100
Subtract the new number by the original number
550 - 571 = -21
-21 ÷ 571 = -0.03677758318739054
-0.03677758318739054 x 100 = -3.68%