Mark Zuckerberg Facebook Inc.’s co- founder and chief executive officer, is no longer one of the world’s 40 richest people. He dropped off from billionaire index. Will he regain his status in billionaire index soon? Is Priscilla Chan lucky enough to bring Mark Zuckerberg fortune back? Is Facebook really worth $100 billion plus?

The 28-year-old’s fortune fell to $14.7 billion today from $16.2 billion on May 25, as shares of the world’s largest social-networking company dropped 9.6 percent to $28.84. That extended the stock’s losses to 24 percent from the worst- performing large initial public offering in the past decade.

“It seems to be a clear reflection that there was just too much stock issued, that the valuation was aggressive and that a lot of people who lined up to buy it really had no intention of holding it,” Jack Ablin, chief investment officer of BMO Harris Private Bank in Chicago, said today in a telephone interview. The bank oversees about $60 billion of assets.

Facebook shares closed at $38.23 on May 18, the first day they began trading, giving Zuckerberg a net worth of $19.4 billion. The Menlo Park, California-based company ended the day with a price-earnings ratio of 83.1, making it more expensive than 99 percent of Standard & Poor’s 500 Index (SPX) stocks. The company went public as the equity index was heading for its biggest monthly decline since September.

Facebook options trading began today, with volume for puts exceeding calls by 1.2 to 1, data compiled by Bloomberg show. More than 200,000 puts were traded, giving the holder the right to sell the shares at a specified price. June $30 puts were the most active contracts, with volume at 23,835. They were followed by June $34 calls and June $32 calls, which carry the right to buy the shares.

Zuckerberg is now $800 million behind Luis Carlos Sarmiento, who ranks 40th with a fortune of $15.5 billion on the Bloomberg Billionaires Index, a daily ranking of the world’s wealthiest people.