Is it possible to pass in several values into a parameter or subreport?

Hello,

I have a field which needs to be selected as a parameter and then passed into multiple subreports using the subreport links. In a few cases, I need several values to be passed in at the same time and for those results for those several values to be combined into one result set. In the remaining cases, just the single value is used. It's easy to create a formula which combines these and then use the formula as a parameter and subreport links, but this is causing Crystal to have to process ALL of the data, over and over and over again. Actually, 4 x 23 times. Ahh! This slows it down too much. How can I pass in multiple values at the same time?

Thanks,

Esther