diff --git a/date_utils/date_utils.go b/date_utils/date_utils.go
index 5bde07f5acdaa505a7cdebd41b7f7e3d0c3c6615..b9f585a6ec2b2896cc7a6bdce7ed3c24b143db5f 100644
--- a/date_utils/date_utils.go
+++ b/date_utils/date_utils.go
@@ -458,7 +458,7 @@ type TradingHoursDay struct {
 }
 
 func (day TradingHoursDay) String() string {
-	if day.StartTime == "" && day.EndTime == "" {
+	if day.StartTime == "" || day.EndTime == "" {
 		return "Closed"
 	}