I got this working by updating your Year Filter field to the following:
if datepart('year',[Order Date]) = datepart('year',[Select Year]) or datepart('year',[Order Date]) = datepart('year',dateadd('year',-1,[Select Year]))
then "Include" else "Exclude" end
I put that on the filter shelf and set it to "Include". Now when a year is selected, that year and the previous year are included.
I've included this in the attached workbook. Let me know if you have any questions.
Filter with Parameter.twbx 2.3 MB
Thats fantastic! I was too concerned trying to match the parameter to the calculation. I didn't think to just create a boolean expression.
Welcome! Happy to help