Drew, thank you so very much. I'd never heard of LAG() or the ROWS UNBOUNDED PRECEDING stuff until now. I love this job because I learn new things every day.

The kicker to this specific project is that I have to check delivery sites for overlapping dates / amounts and error them out. Which would be my next hurdle if I hadn't gotten your help on the "Tying MAX() value" thread for the last project a couple of weeks ago. You just sorted out a whole bunch of problems with two posts. Thank you so very much.