You were very close to your goal. A BES Analysis is considered as a BES Fixlet. To identify that a BES Fixlet is in fact a BES Analysis, there is a specific property named “analysis flag of it”.
So the following relevance will give the list of BES Analyses, followed by the number of applicable computers:
(name of it, number of applicable computers of it) of bes fixlets whose (analysis flag of it)
And if you want the number of applicable computers for a specific BES Analysis, it could be something like:
number of applicable computers of bes fixlets whose (analysis flag of it and name of it =
"<Analysis Name>")