Among the underlying components of the S&P 500 index, we saw noteworthy options trading volume today in Allstate Corp (ALL), where a total of 11,880 contracts have traded so far, representing approximately 1.2 million underlying shares. That amounts to about 58.2% of ALL's average daily trading volume over the past month of 2.0 million shares. Especially high volume was seen for the $180 strike call option expiring April 19, 2024, with 10,390 contracts trading so far today, representing approximately 1.0 million underlying shares of ALL. Below is a chart showing ALL's trailing twelve month trading history, with the $180 strike highlighted in orange:

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

Merck & Co Inc (MRK) saw options trading volume of 52,729 contracts, representing approximately 5.3 million underlying shares or approximately 50% of MRK's average daily trading volume over the past month, of 10.6 million shares. Especially high volume was seen for the $120 strike put option expiring March 28, 2024, with 4,233 contracts trading so far today, representing approximately 423,300 underlying shares of MRK. Below is a chart showing MRK's trailing twelve month trading history, with the $120 strike highlighted in orange:

And Carmax Inc. (KMX) saw options trading volume of 6,352 contracts, representing approximately 635,200 underlying shares or approximately 42.9% of KMX's average daily trading volume over the past month, of 1.5 million shares. Particularly high volume was seen for the $70 strike put option expiring April 19, 2024, with 4,653 contracts trading so far today, representing approximately 465,300 underlying shares of KMX. Below is a chart showing KMX's trailing twelve month trading history, with the $70 strike highlighted in orange: