-1.78% is the change from 506 to 497
Calculation steps:
[( 497 - 506 ) ÷ 506] x 100 = -1.78%
Formula
Percentage change = [(497 - 506) / 506] x 100
Subtract the new number by the original number
497 - 506 = -9
-9 ÷ 506 = -0.017786561264822136
-0.017786561264822136 x 100 = -1.78%