The mistake report is similar to the performance report. It will show how many mistakes of each type you are committing and sum them up for you to see the total number of strokes you are losing per round. There is also a higher level of mistake type and you will see summaries for these as well.
To see your mistake report select "Mistake report" from the "Analysis" menu. There are two graphs you can select, one is the individual mistakes and the other is a summary of mistake types. If you would like to change the graph, select the type from the radio buttons. The new graph will be automatically displayed.