Looking at options trading activity among components of the S&P 500 index, there is noteworthy activity today in Citigroup Inc (C), where a total volume of 158,738 contracts has been traded thus far today, a contract volume which is representative of approximately 15.9 million underlying shares (given that every 1 contract represents 100 underlying shares). That number works out to 61.8% of C's average daily trading volume over the past month, of 25.7 million shares. Particularly high volume was seen for the $55 strike call option expiring April 22, 2022, with 20,521 contracts trading so far today, representing approximately 2.1 million underlying shares of C. Below is a chart showing C's trailing twelve month trading history, with the $55 strike highlighted in orange:

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Today's Most Active Call & Put Options of the S&P 500 »

Franklin Resources Inc (BEN) saw options trading volume of 17,173 contracts, representing approximately 1.7 million underlying shares or approximately 59.1% of BEN's average daily trading volume over the past month, of 2.9 million shares. Especially high volume was seen for the $25 strike put option expiring October 21, 2022, with 9,013 contracts trading so far today, representing approximately 901,300 underlying shares of BEN. Below is a chart showing BEN's trailing twelve month trading history, with the $25 strike highlighted in orange:

And Walmart Inc (WMT) saw options trading volume of 39,389 contracts, representing approximately 3.9 million underlying shares or approximately 51.5% of WMT's average daily trading volume over the past month, of 7.6 million shares. Particularly high volume was seen for the $160 strike call option expiring April 22, 2022, with 12,157 contracts trading so far today, representing approximately 1.2 million underlying shares of WMT. Below is a chart showing WMT's trailing twelve month trading history, with the $160 strike highlighted in orange: