-2.32% is the change from 518 to 506
Calculation steps:
[( 506 - 518 ) ÷ 518] x 100 = -2.32%
Formula
Percentage change = [(506 - 518) / 518] x 100
Subtract the new number by the original number
506 - 518 = -12
-12 ÷ 518 = -0.023166023166023165
-0.023166023166023165 x 100 = -2.32%