MBD revenue increased primarily reflecting sales of the 2010 Microsoft Office system. Business revenue increased $420 million or 9%, primarily reflecting growth in multi-year volume licensing revenue, licensing of the 2010 Microsoft Office system to transactional business customers, and an 11% increase in Microsoft Dynamics revenue. Consumer revenue decreased $251 million or 17% due mainly to the recognition of $224 million of revenue in the prior year associated with the Office Deferral. Excluding the impact associated with the Office Deferral, consumer revenue decreased $27 million or 2% due to decreased sales of the 2010 Microsoft Office system
MBD revenue for the three months ended December 31, 2011 included a favorable foreign currency impact of $131 million.
MBD operating income increased due to revenue growth, offset in part by higher operating expenses. Cost of revenue increased, primarily driven by higher online operation and support costs.