Options Activity Surges for HYG ETF On March 25, the iShares iBoxx $ High Yield Corporate Bond ETF (HYG) saw a trading volume of over 543,000 options, with 96.13% being put options. A notable trade involved 25,000 contracts for a $77 strike price, reflecting $200,000 in turnover. Open interest reached 7.59 million contracts, exceeding the 30-day average.3