NYSE calls for coordination among exchanges to ease volatility

The New York Stock Exchange on Thursday recommended reforms to the US equities market which it said could improve stability and prevent a repeat of the wild price swings seen on August 24 during a near-unprecedented bout of volatility. The measures included a call for all US stock exchanges to modify and coordinate their policies on trading halts when securities prices move violently in a short time.
Such halts were first introduced after the 2010 flash crash when around $1 trillion in paper value was temporarily wiped from US stock markets within minutes. Many investors said the rules failed their first big test on August 24, when panic over the health of the Chinese economy hammered US stock futures prior to the market open, and then triggered a record intraday drop in the Dow Jones industrial average.
During the volatility on August 24 there were 1,278 halts compared to 39 on a typical day, NYSE, which is owned by Intercontinental Exchange Inc, said in its report. Exchange-traded funds that track equities were hit especially hard, and most of the halts happened in the first hour of trading. The sporadic and rapid-fire halts led to confusion among some investors as to what was trading and questions whether they got prices worse than they should have. NYSE said longer trading halts could be used to allow buy or sell imbalances to clear before the stocks reopen to prevent successive halts.
Another of its suggestions was that when a security is halted, all eligible trading interest be sent to the exchange where it is listed, creating a bigger pool of liquidity that allows for more accurate pricing. Unlike other exchanges, which are nearly fully automated, NYSE uses people on its trading floor to open its stocks, a process it says gives it greater stability because the traders can intervene in ways that algorithms cannot. But rivals say NYSE's use of humans rather than computers caused undue delays in opening some stocks and ETFs after they were halted, intensifying ETF pricing issues.
NYSE said it has already instituted changes on its own exchange to prevent further issues, but that it was now time for the industry to act together on market-wide reforms.