Bring number from a Sub Report to the Main Report

[FastEddie]

I am trying to get the 6, which is shown under column B to show where I have the red number circled.



I thought I could go to the Sub Report and do this:

Shared NumberVar colBx = Sum ({@CkColB}, {TicketItems.ServiceCode})

Then on the main form I am trying to get the number like this:

Shared numberVar ColBx

But I am only getting 0's in return. What am I doing wring?