-49.09% is the change from 990 to 504
Calculation steps:
[( 504 - 990 ) ÷ 990] x 100 = -49.09%
Formula
Percentage change = [(504 - 990) / 990] x 100
Subtract the new number by the original number
504 - 990 = -486
-486 ÷ 990 = -0.4909090909090909
-0.4909090909090909 x 100 = -49.09%