diff --git a/core/ajax/cmd.ajax.php b/core/ajax/cmd.ajax.php
index 6e1f905431..7aebdb17f2 100644
--- a/core/ajax/cmd.ajax.php
+++ b/core/ajax/cmd.ajax.php
@@ -385,8 +385,8 @@
 		}
 
 		if ($dateStart == '' && init('dateRange') != 'all') {
-			$now = date('Y-m-d');
-			$dateStart = $now->modify('- ' . init('dateRange'));
+			$now = new DateTime();
+			$dateStart = $now->modify('- ' . init('dateRange'))->format('Y-m-d');
 		}
 
 		$return['maxValue'] = '';