On February 6, 2018, the index surged to 50 in early morning trading before collapsing to 22 shortly before the market opened and then returning to 46 by midday. Market participants say these wild...

On February 6, 2018, the index surged to 50 in early morning trading before collapsing to 22 shortly before the market opened and then returning to 46 by midday. Market participants say these wild swings might simply reflect the lack of trading activity in the underlying S&P 500 options before US stock markets open at 9:30am.