FM - Setting Up a Table of Sales Reports

I've been tasked with importing from Excel sales reports from our tenants.  I started designing per the spreadsheet, but thought I'd ask for best practice.  The spreadsheet is setup with column headings for the months, which translates into separate fields in FM.  However, I think it would give me more flexibility if I had one field for the amount and a field for the month (already planned to have a field for the year).  The drawback is I would have to import one month at a time (so 12 imports) so I could auto enter the month.  See attached screen print (without identifying info).
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