diff --git a/timesheet/inc/class.timesheet_merge.inc.php b/timesheet/inc/class.timesheet_merge.inc.php
index 29b846559e..7402081b7e 100644
--- a/timesheet/inc/class.timesheet_merge.inc.php
+++ b/timesheet/inc/class.timesheet_merge.inc.php
@@ -27,6 +27,15 @@ class timesheet_merge extends bo_merge
 		'timesheet_replacements'	=> true,
 	);
 
+	/**
+	 * Fields that are numeric, for special numeric handling
+	 */
+	protected $numeric_fields = array(
+		'$$ts_duration$$',
+		'$$ts_quantity$$',
+		'$$ts_unitprice$$'
+	);
+
 	/**
 	 * Business object to pull records from
 	 */