>No, I don't want :-)
>Why should I?
>I want to get to this range where the Overweight belongs.
>the PreviousAmount column contains the total of ALL previous ranges and I need to calculate only difference between the Overweight and MinRange.
I see now, OK. So either of the ideas will work, but I like George's for its simplicity and no need for an extra column.
On the other hand, with the PreviousTotalAmount will work quicker - less records to join.
If it's not broken, fix it until it is.
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