Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Netflix Inc (NFLX), where a total volume of 45,456 contracts has been traded thus far today, a contract volume which is representative of approximately 4.5 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 138.9% of NFLX's average daily trading volume over the past month, of 3.3 million shares..