diff --git a/app/src/main/java/org/nsh07/pomodoro/data/StatDao.kt b/app/src/main/java/org/nsh07/pomodoro/data/StatDao.kt
index 3dcba51..f1767f5 100644
--- a/app/src/main/java/org/nsh07/pomodoro/data/StatDao.kt
+++ b/app/src/main/java/org/nsh07/pomodoro/data/StatDao.kt
@@ -42,10 +42,10 @@ interface StatDao {
 
     @Query(
         "SELECT " +
-                "AVG(focusTimeQ1) AS focusTimeQ1, " +
-                "AVG(focusTimeQ2) AS focusTimeQ2, " +
-                "AVG(focusTimeQ3) AS focusTimeQ3, " +
-                "AVG(focusTimeQ4) AS focusTimeQ4 " +
+                "AVG(NULLIF(focusTimeQ1,0)) AS focusTimeQ1, " +
+                "AVG(NULLIF(focusTimeQ2,0)) AS focusTimeQ2, " +
+                "AVG(NULLIF(focusTimeQ3,0)) AS focusTimeQ3, " +
+                "AVG(NULLIF(focusTimeQ4,0)) AS focusTimeQ4 " +
                 "FROM (SELECT focusTimeQ1, focusTimeQ2, focusTimeQ3, focusTimeQ4 FROM stat ORDER BY date DESC LIMIT :n)"
     )
     fun getLastNDaysAvgFocusTimes(n: Int): Flow<StatFocusTime?>