Word doesn't like numerics in the merge data. Convert to strings and all will
work fine. Naturally you'll need to format the strings for proper presenation.
MS Word will require a format picture code on the merge field if a raw
numeric is passed. In addition Word can generate funky results if the raw
numeric value is passed to Word.
See:
http://office.microsoft.com/en-us/assistance/HA011164951033.aspx
Abstract of URL shown above:
"Number formatting problems in a mail merge occur when the cells that
contain the numbers in the Excel worksheet are formatted as Number, Currency,
Date, Percentage, and so on. The solution for getting numbers to behave
properly when you merge is to format as Text the cells that contain numbers.
When cells are formatted as Text, you can type your numbers in the cells
exactly the way you want them to look (with dollar signs, zeros, and so
forth). Then they will merge exactly as you type them."