[Koha] Report help

Hi Everyone, I've been using the report 'Patrons with most checkouts in date range' with success, but when I try to modify it to allow me to select which campus library the patrons are from so I can get a top 20 list for any of our campus libraries, I can't get it to work - can anyone help me with this? SELECT concat(b.surname,', ',b.firstname) AS name, count(s.borrowernumber) AS checkouts FROM statistics s LEFT JOIN borrowers b USING (borrowernumber) WHERE s.datetime BETWEEN <<Top checkouts BETWEEN (yyyy-mm-dd)|date>> AND <<and (yyyy-mm-dd)|date>> GROUP BY s.borrowernumber ORDER BY count(s.borrowernumber) DESC LIMIT 20 Thank you! Kerrie Stevens COLLEGE LIBRARIAN Harvest Bible College