-48.38% is the change from 990 to 511
Calculation steps:
[( 511 - 990 ) ÷ 990] x 100 = -48.38%
Formula
Percentage change = [(511 - 990) / 990] x 100
Subtract the new number by the original number
511 - 990 = -479
-479 ÷ 990 = -0.48383838383838385
-0.48383838383838385 x 100 = -48.38%