Yes, this is possible.  You first select a test type and its index.  Then you check the results you’d like to see on the evolution graph.  You’d typically select ‘Show all’ in the grid.

Then you click on the right mouse button in the background of a graph.  Alternatively, you can  check the Show evolution chart checkbox in the format window.

The selected index is now shown as a function of the test date.

Evolution chart showing the index (1), in this case the score at 70 dBSPL, as a function of time (horizontal axis). 
Events are plotted on the graph if they are selected in the list. 
Event bars contain the event type if they concern the ipsilateral ear (2) ; 
they are empty if they concern the contralateral ear (3). 
The sliders (4) can be moved to zoom in into a specific time window.