-0.5% is the change from 603 to 600
Calculation steps:
[( 600 - 603 ) ÷ 603] x 100 = -0.5%
Formula
Percentage change = [(600 - 603) / 603] x 100
Subtract the new number by the original number
600 - 603 = -3
-3 ÷ 603 = -0.004975124378109453
-0.004975124378109453 x 100 = -0.5%