Looking at options trading activity among components of the Russell 3000 index, there is noteworthy activity today in Generac Holdings Inc (GNRC), where a total volume of 3,818 contracts has been traded thus far today, a contract volume which is representative of approximately 381,800 underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 43.5% of GNRC's average daily trading volume over the past month, of 878,455 shares..