$to = date2sql($to);
$sql = "SELECT SUM(IF(t.type = ".ST_SALESINVOICE." OR (t.type IN (".ST_JOURNAL." , ".ST_BANKPAYMENT.") AND t.ov_amount>0),
- -abs(t.ov_amount + t.ov_gst + t.ov_freight + t.ov_freight_tax + t.ov_discount), 0)) AS charges,";
+ -abs(IF(prep_amount, prep_amount, ov_amount + ov_gst + ov_freight + ov_freight_tax + ov_discount)), 0)) AS charges,";
$sql .= "SUM(IF(t.type != ".ST_SALESINVOICE." AND NOT(t.type IN (".ST_JOURNAL." , ".ST_BANKPAYMENT.") AND t.ov_amount>0),
abs(t.ov_amount + t.ov_gst + t.ov_freight + t.ov_freight_tax + t.ov_discount) * -1, 0)) AS credits,";
$sql .= "SUM(IF(t.type != ".ST_SALESINVOICE." AND NOT(t.type IN (".ST_JOURNAL." , ".ST_BANKPAYMENT.")),