After creating the relationship, Excel will identify those tables as a Data Model Table, not a Worksheet Table in the dropdowns. To see what Excel did, click Manage Data Model in the Data Tools group.

Although you don't have to format your data as an Excel table, doing so will make life easier if you add more rows or columns, and Excel generally reads data formatted as a table ...

Double-click the Excel file containing the data for which you want to create a cumulative chart. Click your mouse cursor on the uppermost cell in one of the columns, and then drag the mouse until ...