[Koha] Extracting Marc Tag 245b for remainder of title in Access

Hey folks. I'm trying to build a report in Access (don't ask me why). I know in Koha, I can use ExtractValue(bi.marcxml, '//datafield[@tag="245"]/subfield[@code="b"]') to get the remainder of the title in the Marc record. However, ExtractValue isn't a function in Microsoft Access. Anyone know of an equivalent method for retrieving this piece of information in an Access report? Christopher Brannon Coeur d'Alene Public Library