The required formula field (not formfield) would be encoded along the lines of:
{=twodogscooter*{={IF{REF Dropdown1}= "Y*" 10 0}+{IF{REF Dropdown2}= "Y*" 10 0}+{IF{REF Dropdown3}= "Y*" 10 0}} \# 0}

Note: The field brace pairs (i.e. '{ }') for the above example are all created in the document itself, via Ctrl-F9 (Cmd-F9 on a Mac); you can't simply type them or copy & paste them from this message. Nor is it practical to add them via any of the standard Word dialogues. The spaces represented in the field construction are all required.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]