Crosstab Object

Hi,

I have clinical data on young patients. The pertinent data is:

Clinic

Patient ID

Age

Vision Screening (1 or 0 for yes/no)

Stereopsis Screening (1 or 0 for yes/no)

I am trying to create a chart using the Crosstab Object. For each clinic I would like:

Clinic Total Patients Total 4 Year Olds Total 4 Year Olds Vision Screened % 4 Year Old Vision Screened...

The ... is the same information for Stereopsis Screened.

The % 4 Year Old Vision Screened is the Total 4 Year Olds/Total 4 Year Olds Vision Screened

In my Cross Tab Expert I have Clinic for Rows.

For summarized fields I have

Count of Patient Id

Sum of 4 Year Olds (4 Year Olds is a formula that say If age = 4 then 1 else 0

Sum of 4 Year Olds With Vision Screening (4 Year Olds With Vision Screening is a formula that says If age = 4 and Vision Screening = 1 then 1 else 0)

I can't find a way in the Crosstab Expert to let me define a Summarized field that is Sum of 4 Year Olds With Vision Screening /

Sum of 4 Year Olds .

If I can get that then I can get the rest.

Thanks,

Dick