Crystal Reports Referencing the result of a running total field

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     Hi,

Novice user simple question again!

I'm using a Running Total Field which returns the highest number in my table and this works fine (using Maximum).

From another table, I wish to show the date of this highest return, but I cannot work out how to do this?

For example, between 30th June and 31st July, my highest price was 425 and my report shows this.  The price was achieved on 15th July, my question is, how can I get Crystal to show this date in my report?

Thanks loads in anticipation for any help here.