Warren Edward Buffett (born August 30, 1930 in Omaha, Nebraska, United States) is an American investor, businessman, and philanthropist. He is one of the world's most successful investors and the largest shareholder and CEO of Berkshire Hathaway. He was ranked by Forbes as the richest person in the world during the first half of 2008, with an estimated net worth of $50.0 billion. Often called the "Oracle of Omaha," or "the Sage of Omaha", Buffett is noted for his adherence to the value investing philosophy and for his personal frugality despite his immense wealth. His 2006 annual salary was about $100,000, which is vanishingly small compared to senior executive remuneration in comparable companies. When Buffett spent $9.7 million of Berkshire's funds on a private jet in 1989, he jokingly named it "The Indefensible" because of his past criticisms of such purchases by other CEOs. He lives in the same house in the central Dundee neighborhood of Omaha that he bought in 1958 for $31,500, today valued at around $700,000. Buffett also is a notable philanthropist. In 2006, he announced a plan to give away his fortune to charity, with 83% of it going to the Bill & Melinda Gates Foundation. In 2007, he was listed among Time's 100 Most Influential People in The World. He also serves as a member of the board of trustees at Grinnell College.