We’ve been hard at work writing a few new tutorial articles to help explain how you can control how accounts appear on reports and dashboards.
One set of tutorials explain how you can create a mapping table to add additional rows to your Profit and Loss, and Balance Sheet Reports for both Power BI and Excel.
How to use a mapping table to group accounts in your Power BI dashboard
How to use a mapping table to group accounts in your Excel Reports

Another tutorial explains how you can edit the account totals on standard OdataLink templates to add additional totals such as EBITDA, EBIT and Gross Profit %.
How to edit the account totals on standard OdataLink templates

Finally and unrelated to the other two, there is also an article describing how you can create calculated tables using DAX in Excel.