diff --git a/models/acc_operation.py b/models/acc_operation.py
index 8be86940f041f56060673cd55f51146834b49556..9bfe32e10e6975e13a67d45dcc14104d23a77a2a 100644
--- a/models/acc_operation.py
+++ b/models/acc_operation.py
@@ -160,15 +160,15 @@ class AccOperation(models.Model):
         step_display_curve = "hour"
         # Calculate delta between 2 dates
         delta = (end_date - start_date).days
-        if delta < 32:
+        if delta > 1 and delta < 32:
             step_display_curve = "day"
             display_hourly_curves = True
+        elif delta >= 32 and delta <= 366:
+            step = "month"
+            step_display_curve = "month"
         elif delta > 366:
             step = "year"
             step_display_curve = "year"
-        else:
-            step = "month"
-            step_display_curve = "month"
 
         return display_hourly_curves, step, step_display_curve