Creating and Editing Summary Time Periods
You can change such aspects as name, description, alias, starting period, and ending period. However, you can't change the order of base time periods or skip base time periods. The range can't extend beyond the current fiscal year.
You must work from the top of the hierarchy to the bottom when creating summary time periods. (Otherwise, the application views the rollup structure as asymmetrical and you can't continue.) The summary time period displays in the hierarchy as a parent of the selected item. To enforce a balanced hierarchy, all base members must be the same number of levels from the root.
To create or edit summary time periods: