Hi Marie GPG, 

You can absolutely compare more than one period at a time, and depending on how you want to achieve this there can be a few different reports to take a look into. 

If you're looking to see the figures for multiple periods at once but are not looking to see their comparison, then you can just change the grouping of the columns on the report that you are looking at. In this case, for the balance sheet, you can run the regular Balance Sheet report, and then in the top left under the date range, change the Display Columns By setting from Total only to Calendar Quarters or Fiscal Quarters, or however you would like to separate the columns to compare the values. Then you'll just need to set the date range of the report to include all of the quarters that you want to display - then when you run the report it will display the data from that report period separated into quarterly amounts. 

If you want to include the comparison values, change percentages etc. in addition to this, you can either enable the "Compare another period" options at the top of the page, or you can similarly change the columns setting from with a report such as the Balance Sheet Comparison report. Using these settings, you should be able to customise the report to display the periods that you are looking for - if you still have any questions, don't hesitate to reply in this thread and we'll be happy to help out further!

-Lucas