diff --git a/Lesson08/Activity15/Activity15.sql b/Lesson08/Activity15/Activity15.sql
index 70c9ed6..b307f8e 100644
--- a/Lesson08/Activity15/Activity15.sql
+++ b/Lesson08/Activity15/Activity15.sql
@@ -14,9 +14,9 @@ sqlda$# SELECT AVG(sales_amount) FROM sales INTO sales_avg WHERE sales_transacti
 -- Return the function variable, end the function and specify the language
 
 sqlda$# RETURN sales_avg;
-sqlda$# END; $channel_avg$
+sqlda$# END; $sales_avg$
 sqlda-# LANGUAGE PLPGSQL;
 
 -- Use the function to determine the average sales value since 2013-04-12
 
-sqlda=# SELECT avg_sales_since('2013-04-12', '2014-04-12');
+sqlda=# SELECT avg_sales_window('2013-04-12', '2014-04-12');