diff --git a/internal/infra/partition/configuration.go b/internal/infra/partition/configuration.go
index 50c80e9..f1240ff 100644
--- a/internal/infra/partition/configuration.go
+++ b/internal/infra/partition/configuration.go
@@ -128,7 +128,8 @@ func (p Configuration) getPrevDate(forDate time.Time, i int) (t time.Time, err e
 		t = time.Date(year, month-time.Month(i), 1, 0, 0, 0, 0, forDate.Location())
 	case Quarterly:
 		year, month, _ := forDate.Date()
-		quarterStartMonth := (month-1)/3*3 + 1
+		quarter := (int(month) - 1) / nbMonthsInAQuarter
+		quarterStartMonth := time.Month(quarter*nbMonthsInAQuarter + 1)
 		t = time.Date(year, quarterStartMonth-time.Month(i*nbMonthsInAQuarter), 1, 0, 0, 0, 0, forDate.Location())
 	case Yearly:
 		year, _, _ := forDate.Date()
@@ -153,7 +154,8 @@ func (p Configuration) getNextDate(forDate time.Time, i int) (t time.Time, err e
 		t = time.Date(year, month+time.Month(i), 1, 0, 0, 0, 0, forDate.Location())
 	case Quarterly:
 		year, month, _ := forDate.Date()
-		quarterStartMonth := (month-1)/3*3 + 1
+		quarter := (int(month) - 1) / nbMonthsInAQuarter
+		quarterStartMonth := time.Month(quarter*nbMonthsInAQuarter + 1)
 		t = time.Date(year, quarterStartMonth+time.Month(i*nbMonthsInAQuarter), 1, 0, 0, 0, 0, forDate.Location())
 	case Yearly:
 		year, _, _ := forDate.Date()