Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Best Buy Inc (BBY), where a total volume of 48,165 contracts has been traded thus far today, a contract volume which is representative of approximately 4.8 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 116.4% of BBY's average daily trading volume over the past month, of 4.1 million shares..