-54.95% is the change from 999 to 450
Calculation steps:
[( 450 - 999 ) ÷ 999] x 100 = -54.95%
Formula
Percentage change = [(450 - 999) / 999] x 100
Subtract the new number by the original number
450 - 999 = -549
-549 ÷ 999 = -0.5495495495495496
-0.5495495495495496 x 100 = -54.95%