CEOs, venture backers lose big as LinkedIn, Tableau shares tumble

By Luc Cohen NEW YORK (Reuters) - LinkedIn Corp Executive Chairman Reid Hoffman lost almost half his $2.8 billion fortune on paper Friday as shares of his social media company suffered their largest drop on record. Other executives at LinkedIn, some at business analytics company Tableau Software Inc, and a number of the companies' venture capital backers also took losses running into tens of millions of dollars as both stocks tumbled on dismal financial outlooks. It was a humbling moment highlig