### Comment:
Great post thank you. 
  
 Actually I believe there is a rule about trading algorithms and this 200 point hit (20 S&amp;P) does raise the question as to legality again.   
  
 FWIW- my check of stocks at the time indicated ALL S&amp;P 500 stocks were hit at once, to the minute.  And it happened at the same time as the Bloomberg news release -to the minute.  Big, powerful system- whoever’s it was. 
  
 Thanks again.

### REPLY:
They were trading the S&amp;P index or S&amp;P futures, which affects the price of all stocks in the index. Trading firms pay news sources like Bloomberg and Reuters for fast and direct access to news feeds, and set algorithms to trade off of that info. 
  
 I don't know that there's rules against it, but they are definitely doing it. Once they do it, others react to the moves, making the effect larger.

### END.