Hi gregpnoonan, 

The Profit and Loss report does not have the option to include GST amounts in the figures by design, however there is a report called Transaction Detail by Tax Code which will show you a breakdown of all of the transactions for a period broken down by the tax code that is allocated to it. This should be able to show you the information that you need, however feel free to reply if you have any other information that you'd like to see. 

-Lucas