According to my Tradestation quote, daily SPX data is not showing the gap down this morning. SPX opened at 1109.78-- almost at Friday's close and then slipped down fast. But ES opened about 6 points down (931 am EST)with respect to 4pm EST Friday's close. I'm wondering what other vendors are showing for SPX open this morning. Thanks, Chinook
Depends on who/how the cash index is calculated - carrying over the Friday close to the open price is common. However, some quote sources don't record their "open" for the cash index until about 9:45am ET because not all index component stocks open for trading at exactly 9:30am ET. Technically, the "open" of the cash index would be the prior day's close and then it ramps/drops from there over the next bunch of minutes as the component stocks each open and start trading.
Thanks for the explanation. I checked Yahoo and it's showing SPX open at 1,103.62 about 6 points lower than TS. However, TS open for Nasdaq Comp. is in line with Yahoo. Chinook