diff --git a/academic_account_interests/__manifest__.py b/academic_account_interests/__manifest__.py
index ca893908..79bddc00 100644
--- a/academic_account_interests/__manifest__.py
+++ b/academic_account_interests/__manifest__.py
@@ -19,7 +19,7 @@
 ##############################################################################
 {
     'name': 'Academic Account Interests',
-    'version': "18.0.1.0.0",
+    'version': "18.0.1.1.0",
     'sequence': 14,
     'summary': '',
     'author': 'ADHOC SA',
diff --git a/academic_account_interests/models/res_company_interest.py b/academic_account_interests/models/res_company_interest.py
index 39fce7aa..de0f7aae 100644
--- a/academic_account_interests/models/res_company_interest.py
+++ b/academic_account_interests/models/res_company_interest.py
@@ -36,7 +36,7 @@ def _calculate_debts(self, from_date, to_date, groupby=['student_id', 'partner_i
             aggregates=['amount_residual:sum'],
         )
         for x in previous_grouped_lines:
-            self._update_deuda(deuda, x[0], 'Deuda periodos anteriores', x[2] * self.rate)
+            self._update_deuda(deuda, x[0], 'Deuda periodos anteriores', x[2] * self.rate * self.interval)
             deuda[x[0]]['partner_id'] = x[1]
 
         # Intereses por el último período
@@ -45,7 +45,7 @@ def _calculate_debts(self, from_date, to_date, groupby=['student_id', 'partner_i
         )
         for student, amls in last_period_lines.grouped('student_id').items():
             interest = sum(
-                move.amount_residual * ((to_date - move.invoice_date_due).days - 1) * (self.rate / interest_rate[self.rule_type])
+                move.amount_residual * ((to_date - move.invoice_date_due).days) * (self.rate / interest_rate[self.rule_type])
                 for move, lines in amls.grouped('move_id').items()
             )
             self._update_deuda(deuda, student, 'Deuda último periodo', interest)