How calculate the simulated capacitance of coaxial

How could I calculate the simulated Capacitance of a coaxial with HFSS?

I don't want to calculate the theoretical result. I want the capacitance obtained by HFSS (Approximated).

Thank's for all and Regards.

It's very simple. You need to use in Report field a Output Variable the next type:
Cap=(-1/(2*pi*freq*im(Z(1,1))))*10^12.
For this Variable you can make a plot or a table.
The result's unit will in pF.
Good luck!

Please Help me!
I don't get the theoretical value of the capacitance with that formule, why?

Please Help me!
I don't get the theoretical value of the capacitance with that formule, why?