-39.63% is the change from 911 to 550
Calculation steps:
[( 550 - 911 ) ÷ 911] x 100 = -39.63%
Formula
Percentage change = [(550 - 911) / 911] x 100
Subtract the new number by the original number
550 - 911 = -361
-361 ÷ 911 = -0.39626783754116357
-0.39626783754116357 x 100 = -39.63%