The Current Period selection criteria can be used to define which results will be included in the Cumulative (ie BOT to Current Period Begin Date - 1 day) and which data will be included in the Current Period sections of this report.   In this version of the Date control, you have the option of specifying:

Note that if you have enabled the Allow Creation of and Show Fiscal Calendar Options (unanet.fiscal_calendar.enabled) property, additional fiscal period options will be available in the dropdown.  
Fiscal periods must be established via the Admin > Setup > Fiscal Year screen in order to be available for use in reporting.  Specific Fiscal Periods appearing in dropdown lists will be a concatenation of Fiscal Year Name with Accounting Period.