D&C Other revenue increased $294 million or 18%, due mainly to an increase in online advertising revenue and Subscription revenue. Online advertising revenue increased $144 million or 16%. Search advertising revenue increased 38%, due primarily to increased revenue per search resulting from ongoing improvements in advertising products and higher search volume, offset in part by a 24% reduction in display advertising revenue. Subscription revenue was $98 million for the three months ended March 31, 2014, reflecting subscriber growth of Office 365 Home.
D&C Other gross margin increased $111 million or 26%, due to an increase in revenue, offset in part by a $183 million or 15% increase in cost of revenue. D&C Other cost of revenue grew, due mainly to a $123 million or 21% increase in online advertising cost of revenue, reflecting support of online infrastructure.