The Chicago Board Options Exchange said it plans to expand its volatility-index franchise, aiming to lure more traders to an area where it already leads its competition.

The exchange, part of CBOE Holdings Inc., said in a release Wednesday that it plans to list options on single-stock volatility measures and to extend the franchise to a raft of sector exchange-traded funds. The CBOE Volatility Index, or VIX, is often called the “fear index” and is the most widely followed gauge of investor expectations for stock-market swings. Get the full story »