Inserting data table in combo graph

I have been able to create a combo graph (bar and line) but when I change the chart type to combo, my data table disappears.  I am reporting a rate in % as a bar graph with the goal rate % as a line graph.  I would like to show the rate data below the chart in a data table.  I click on insert data table and nothing happens.  Any suggestions?  Is my only option to use data labels?