diff --git a/src/Collections/ProjectionCollection.php b/src/Collections/ProjectionCollection.php
index ca8b4f9..4eade7f 100644
--- a/src/Collections/ProjectionCollection.php
+++ b/src/Collections/ProjectionCollection.php
@@ -196,7 +196,7 @@ private function getAllPeriods(Carbon $startDate, Carbon $endDate, string $perio
         [$periodQuantity, $periodType] = Str::of($period)->split('/[\s]+/');
 
         while ($cursorDate->notEqualTo($endDate)):
-            $cursorDate->add($periodQuantity, $periodType);
+            $cursorDate->add((float)$periodQuantity, $periodType);
 
             if ($cursorDate->notEqualTo($endDate)) {
                 $allProjectionsDates->push(clone $cursorDate);