-39.64% is the change from 999 to 603
Calculation steps:
[( 603 - 999 ) ÷ 999] x 100 = -39.64%
Formula
Percentage change = [(603 - 999) / 999] x 100
Subtract the new number by the original number
603 - 999 = -396
-396 ÷ 999 = -0.3963963963963964
-0.3963963963963964 x 100 = -39.64%