diff --git a/pkg/types/core_time.go b/pkg/types/core_time.go
index 1729ecb8a6..554fd00ebb 100644
--- a/pkg/types/core_time.go
+++ b/pkg/types/core_time.go
@@ -495,8 +495,6 @@ func mixDateAndDuration(date *CoreTime, dur Duration) {
 	date.setDay(uint8(day))
 }
 
-var daysInMonth = []int{31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
-
 // getDateFromDaynr changes a daynr to year, month and day,
 // daynr 0 is returned as date 00.00.00
 func getDateFromDaynr(daynr uint) (year uint, month uint, day uint) {
@@ -527,7 +525,7 @@ func getDateFromDaynr(daynr uint) (year uint, month uint, day uint) {
 	}
 
 	month = 1
-	for _, days := range daysInMonth {
+	for _, days := range daysByMonth {
 		if dayOfYear <= uint(days) {
 			break
 		}