REDMOND, Wash., Oct. 23 /PRNewswire-FirstCall/ -- Microsoft Corp. today announced revenue of $12.92 billion for the first quarter ended Sept. 30, 2009, a 14% decline from the same period of the prior year. Operating income, net income and diluted earnings per share for the quarter were $4.48 billion, $3.57 billion and $0.40 per share, which represented declines of 25%, 18% and 17%, respectively, when compared with the prior year period.