-2.15% is the change from 511 to 500
Calculation steps:
[( 500 - 511 ) ÷ 511] x 100 = -2.15%
Formula
Percentage change = [(500 - 511) / 511] x 100
Subtract the new number by the original number
500 - 511 = -11
-11 ÷ 511 = -0.021526418786692758
-0.021526418786692758 x 100 = -2.15%