diff --git a/erpnext/stock/report/stock_ageing/stock_ageing.py b/erpnext/stock/report/stock_ageing/stock_ageing.py
index ff603fc..623dc2f 100644
--- a/erpnext/stock/report/stock_ageing/stock_ageing.py
+++ b/erpnext/stock/report/stock_ageing/stock_ageing.py
@@ -49,7 +49,7 @@
 	for batch in fifo_queue:
 		batch_age = date_diff(to_date, batch[1])
 
-		if type(batch[0]) in ['int', 'float']:
+		if isinstance(batch[0], (int, float)):
 			age_qty += batch_age * batch[0]
 			total_qty += batch[0]
 		else:
@@ -302,4 +302,4 @@
 		fieldname=fieldname,
 		fieldtype=fieldtype,
 		width=width
-	))
\ No newline at end of file
+	))