Consider this example:
Say after calculating subtotals by week I then want to add sales data for more weeks (initially we had Week1...Week5 and I would like to add Week6, Week7, Week8) and have them sub-totaled the same way BUT I don't want any changes to previously calculated subtotals.
What is the proper way to do this (if it is even possible)?
The only way I found is this (I use Excel 2007): select all cells, press "Subtotal", press "Remove All", then re-sort by "Week" and generate sub-totals for the whole table from scratch. Problem with this approach is that it recalculates existing sub-totals which is what I want to avoid.