It would look something like this
PartNumber 1
Month 1 Month 2 Month 3
Total 1 Total 2 Total 3
PartNumber 2
Month 1 Month 2 Month 3
Total 1 Total 2 Total 3
Sql for the qry is
SELECT tblPartNumber.PartNumber, Sum(tblProductUsageDetails.Quantity) AS Total, DatePart("m",[Date]) AS [Month]
FROM tblPartNumber INNER JOIN tblProductUsageDetails ON tblPartNumber.PartNumberID = tblProductUsageDetails.ProductFK
WHERE (((tblProductUsageDetails.Date) Between #1/1/2007# And #12/31/2007#))
GROUP BY tblPartNumber.PartNumber, DatePart("m",[Date])
ORDER BY tblPartNumber.PartNumber, DatePart("m",[Date]);