Convert my line chart to stack chart by add 1 more field diamension it display wrong value

[paulyeo11]

Hi All

I have a Table (A) which display which display stock amount by month , 2 type of stock amount are shown for the last 10 month.

I manage to convert Table (A) to chart (A) which display the overall stock amount by month.

Now i need to convert the Chart (A) to stack chart , for show the Stock amount by month by 2 type of stock , but i am not able to make it display correctly.

Hope some one can advise me.

Paul