Do all records have either a "Yes" or a "No"? Or do some records have nothing in that field? If all records have either "Yes" or "No", just perform a find for records that have "Yes" and then you have the set of records for your report. If some records are blank in that field, then perform a find that omits records that have a "No" and again you have the set of records for your report (some with have "Yes" and some will be blank, but you won't have any records with "No"). This process can also be scripted if you wish.
if you already have a "found set" (by date or something), you can CONSTRAIN with the "yes".