GL 7999 is a Summary GL Account that reflects the Net Income/Loss as shown on the Income Statement, as at the Balance Sheet date.
When a year-end close procedure is performed in Brief Accounting, the Profit & Loss GL 7999 is closed to Retained Earnings GL 3999.
If an Income Statement is printed for the Open Period, GL 7999 will match the Net Income/Loss on the Income Statement.
To check the Open Period start date:
Choose the Company module > GLSetup tab
Note the "Current Fiscal Year Start Date"
This is the start date for the Open Period.