Today & this time last year comparison

I see that WD has a today/yesterday comparison table of records, but how difficult would it to create a file that could show today’s date compared to this same date last year. Would also be good to have one for monthly date comparisons, but then what will happen for leap years which have an additional date as well as those months which either have 30 or 31 days.

the trends has this
i.e last year is a comparison with the same time and day 1 year ago
(same thing for last month)