USA Today: Facebook founder and CEO Mark Zuckerberg celebrated his 31st birthday Thursday. What a year he’s had — not many people make $1.2 billion on their birthday. Shares of the No. 1 social media company jumped $2.93, or 3.7%, to $81.37 Thursday. That’s a $1.2 billion gain for Zuckerberg, who owns 426.3 million shares. The company and stock flourished under the CEO during his 30th year, rocketing 37.4%. No one benefitted more than the Zuck. Zuckerberg’s shares jumped $9.4 billion in value over the past year. This doesn’t even include the $610,455 he was paid last year for serving as CEO. That sure eases the pain of getting a year older.