Rolling 12 month total over multiple worksheets and multiple sum columns

Hi there!

I have a pilot's logbook spreadsheet that I have made. The workbook is made up of multiple sheets, one per year (i.e. 2007, 2008, 2009, etc.) and then one summary sheet. On the summary sheet, I am trying to figure out how to make a rolling total of the flying hours of the last 12 months, 6 months, 3 months and 1 month. I can't figure out how to do it not only over multiple sheets but also over multiple columns in the sum range (I need to sum from M4:Z200). I would like the totals to automatically update every day as time progresses. The dates for each flight are contained within cell C, which is a date formatted to show as a day of the week.

This is my first time using this forum, I apologise if there isn't enough detail, I will gladly add more if needed!

Thank you in advance for your help.