I'm having an issue and I'm hoping someone can help.

I have a lost with two columns, the first column is the size of a suite (in watts), and the second column is the number of suites of that type. What I need to do is order the size of the suites from highest to lowest, and also have the number of suite types change as well. I can order the suite size using the LARGE function but I can't figure out how to get the number of suites to correspond correctly to the suite size. The suite size can change based on several user inputs so I think I have to avoid ordering the list with the sort function.

Ultimately what I'm trying to do is order the suite sizes from highest to lowest, and then sum the suites as follows: (Size of largest suite) @ 100% + (size of next 2 largest suites) @ 65% + (Size of next 2 largest suites) @ 40% + (Size of next 15 largest suites) @ 25% + (size of all remaining suites) @ 10%.
Basically suite derating as per the Canadian Electrical Code.

If anyone could help on any part of this I would appreciate it,
Thanks.