diff --git a/app/code/core/Mage/Catalog/Model/Resource/Category/Flat.php b/app/code/core/Mage/Catalog/Model/Resource/Category/Flat.php
index 942c5a8afcf..db14c317071 100644
--- a/app/code/core/Mage/Catalog/Model/Resource/Category/Flat.php
+++ b/app/code/core/Mage/Catalog/Model/Resource/Category/Flat.php
@@ -1233,19 +1233,15 @@ public function getChildrenAmount($category, $isActiveFlag = true)
 
     /**
      * Get products count in category
-     *
-     * @param  Mage_Catalog_Model_Category $category
-     * @return int
      */
-    public function getProductCount($category)
+    public function getProductCount(Mage_Catalog_Model_Category $category): int
     {
         $select =  $this->_getReadAdapter()->select()
             ->from(
                 $this->getTable('catalog/category_product'),
                 "COUNT({$this->getTable('catalog/category_product')}.product_id)",
             )
-            ->where("{$this->getTable('catalog/category_product')}.category_id = ?", $category->getId())
-            ->group("{$this->getTable('catalog/category_product')}.category_id");
+            ->where("{$this->getTable('catalog/category_product')}.category_id = ?", $category->getId());
         return (int) $this->_getReadAdapter()->fetchOne($select);
     }