How do I graph "open" items in Excel based on dates?

I have an open date and an close date (or a null if it's not closed yet) for orders and I need to graph the "open" order total for each day for an entire year. Meaning, it calculates every order that is open on every date whose close date is in the future or null. Any ideas?|||A Pivot Table is probably what you need to use as it can process data by category to produce summaries and other reports.