The Microsoft Support and Services team offers some help with Microsoft Dynamics GP Year-End Release 2012: Inventory Control Year End Close
Microsoft Dynamics GP Year-End Release 2012: Inventory Control Year End Close
Year-End & 1099General Ledger & FinancialsSales, Purchasing & Inventory
Archived post from 2012. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.