sudden market behaviour


Junior member
10 0
Yesterday on US 11am, the Dow Jones dropped 100 points within a blink, just a flash, the number changed from more than 8200 to 8080.

I wonder if the index is calcuated based on the 30 companies prices, will the selling pressue push the index down 100 points within 0.5 second?

Where is the selling pressure coming from? huge fund manager? or millions of normal stock holders sending selling orders at the same time?


Experienced member
1,879 313
Yes, if you've got a program trade loaded that will hit the bids in X size in all 30 stocks.

Now imagine about 20 different firms doing that at the same time

Jack o'Clubs

Experienced member
1,554 342
very fast action like that is usually driven by futures selling, and then the arbs/program trades dump stocks to remain in synch.
AdBlock Detected

We get it, advertisements are annoying!

But it's thanks to our sponsors that access to Trade2Win remains free for all. By viewing our ads you help us pay our bills, so please support the site and disable your AdBlocker.

I've Disabled AdBlock