diff --git a/src/calculation_time_constrains/service.py b/src/calculation_time_constrains/service.py
index 1edc105..c8e2d0b 100644
--- a/src/calculation_time_constrains/service.py
+++ b/src/calculation_time_constrains/service.py
@@ -142,6 +142,7 @@ class ReliabilityService:
             if month_count == 0:
                 cumulative_failures = 0
                 results[last_day_date] = round(cumulative_failures, 3)
+                month_count += 1
                 continue
 
             # Stop if we've passed the end_date