Using a subreport value in the main report

I am fairly new to Crystal. I am using version 10.

I have a sub report that pulls in a date from a table.

I need to use the date in a formula as part of the main report.

Subreport
Create_Date

Main Report
Sale_Date

Formula to be used in main report
{CLY.Create_Date} <= {SLX.Sale_Date} = Yes

Can this be done?

You can do it thru Shared Variables
The next are links where you can find useful information about it
Also there is the Crystal Reports help

http://it.toolbox.com/wiki/index.php/Shared_Variables
http://www.ehow.com/how_5287432_use-...al-report.html

JG