Index: monitoring-plugins-2.4.0/plugins/check_ntp_time.c
===================================================================
--- monitoring-plugins-2.4.0.orig/plugins/check_ntp_time.c
+++ monitoring-plugins-2.4.0/plugins/check_ntp_time.c
@@ -532,7 +532,7 @@ int process_arguments(int argc, char **a
 }
 
 char *perfd_offset (double offset) {
-	return fperfdata ("offset", offset, "s",
+	return fperfdata ("offset", fabs(offset), "s",
 		true, offset_thresholds->warning->end,
 		true, offset_thresholds->critical->end,
 		false, 0, false, 0);