Circuit Breakers, but no Curbs

Posted today at RealMoney:

David Merkel
Bye-bye to Trading Curbs
11/7/2007 2:37 PM EST

When the NY Composite fell 2% today, no trading curbs kicked in. Program trading went on unfettered by a need for upticks. Around 1:20, when the curbs would have kicked in, the market fell a little, stabilized, and began to rally. So much for the curbs. Now all that remains are the circuit breakers, which kick in when the DJIA is down 10% and 20%. The circuit breakers only came into existence in 1987, and to the best of my knowledge, have never been triggered. (Anyone else know for sure? I don’t have intraday data.)

Using closing data since 1900 (again, I don’t have intraday), the circuit breakers would have been triggered 5 and 2 times each. That’s once every 21 and 54 years, respectively. To me, that’s not frequent enough to have a rule in place, even if intraday data would double the frequency.

Position: none

As it was, the market finished down nearly 3% today.  I suspect that curbs wouldn’t have helped much, but who can tell.  The market is a lot more game-friendly than it used to be; far fewer rules to observe (or flout).

On an unrelated note, here are my two REIT charts from yesterday, in thumbnail form, for those who had a hard time with them yesterday.

Mortgage REITs

Mortgage REIT yield spread

Equity REITs

Equity REIT Yield Spread