understanding profit

[CIBIR Corporation <CIBIR@xxxxxxxxxxxxxxxx>]

We you purchase an option on a contract you pay X amount of dollars for the
option.  Now once your option is "in the money", how do you calculate your
profit?  I have Metastock with Reuters and am trying to keep an eye on the
profit that I am making while paper trading.  I recently "bought" a
December 97 370 Call, well today it went "in the money" and I am trying to
figure out from the Returers info how much I "made" from this so far.

Thanks

Joe