import module namespace math="http://www.zorba-xquery.com/modules/math"; math:subtotal(8, (1345, 1301, 1368, 1322, 1310, 1370, 1318, 1350, 1303, 1299)) (: Expected output: <?xml version="1.0" encoding="UTF-8"?> 26.054558142482477 :)