Sometimes data values are shown in the data table but do not display properly or don't appear at all in a graph object. This is usually caused by one of two things: improper scaling of graph axes or the desired data column or run is not selected in the Y-axis selection dialog.
Make sure the graph is selected. Click the Autoscale button on the toolbar to scale the axes to fit the data.
To select the data column you want, click the label of the y-axis the to access the Y-Axis Options dialog, where you can select the column you want plotted on the graph.