-49.45% is the change from 550 to 278
Calculation steps:
[( 278 - 550 ) ÷ 550] x 100 = -49.45%
Formula
Percentage change = [(278 - 550) / 550] x 100
Subtract the new number by the original number
278 - 550 = -272
-272 ÷ 550 = -0.49454545454545457
-0.49454545454545457 x 100 = -49.45%