Nanex ~ 15-Aug-2012 ~ HFT Doesn't Harm Investors
and Other Absurdities
From the 1990's through the end of 2006, electronic trading increased transparency which attracted liquidity, leading to to narrower spreads and greater market stability. The graphic in this recent New York Times article shows the steady reduction in trading costs up until about 2006. Since that time, trading costs have not changed significantly on the execution side but on the analysis side (not factored into the New York Times article), both the number of quotes and the cost of receiving and processing them has exploded.1 Spreads have also become considerably less stable.
The Beginning of TurmoilStarting around 2007, two developments began which would slowly erode transparency, market stability and confidence in the market. It was also the beginning of an explosion in stock quotes (but not stock trades) and an era of micro-crashes, mini-crashes, flash crashes, IPO opening day disasters and algos running unchecked that could destroy a major Wall Street firm in 30 minutes.
Those two developments were:
To be sure, there is considerable debate about when HFT began, and this arises because HFT means different things to different people. Most HFT proponents latch on to this confusion and try to claim benefits from transparent electronic trading as benefits from HFT. But one thing most people agree on, is that HFT is a subset of electronic trading.
The term High Frequency Trading first shows up on Google Trends near the beginning of 2008, with wide-spread use starting July 2009. One common feature of HFT is co-location, which is the practice of running your trading computer in the same room as the exchange computers. Co-location became more wide-spread after the adoption of Reg NMS which provided fair and equal access of exchange market data to any market participant. Reg NMS was adopted in early 2007.
Up until about 2006, the primary source of latency, or delay in processing market trading data came from the speed of computers and networks. Wall Street has always bought the fastest computers available, being among the first industries to adopt the latest technology. Faster computers meant faster processing which meant less delay occurred between receiving market data and trading on it.
After about 2006, computers and networks reached speeds where the distance between the trading computer and exchange computer started to matter. This is because light, and thus information, has a distinct maximum speed of approximately 186 miles (300km) per millisecond (ms). If a computer takes 50 ms to process and act on market data, and the trading computer is 186 miles away, the actual time from information to trade is 52 ms (1 ms to receive + 50 ms to process + 1 ms to transmit). Some would add another millisecond for trade confirmation. Thus a trading computer located 186 miles from the exchange has a disadvantage of 2 ms or 4% due to the speed of light, which is probably not enough to matter. But if the processing time drops to 1 ms, the speed of light disadvantage balloons to 66%, and now location is paramount.
Once computer technology dropped processing time below about 10 ms, co-location offered a significant advantage to those within the exchange room versus those outside this "inner circle". Left essentially unchecked2 from any market regulation or oversight, programmers exploited this advantage in every way possible, and we can see the results every trading day.
At first, the simple speed advantage was enough to earn fat profits. But as the HFT field became crowded with new participants, the easy profits were gone, and creating and exploiting new speed advantages and opportunities began. There are many ways to accomplish this. One way to do this is slow down some computers or networks by sending a higher number of orders at crucial time, a practice known as Quote Stuffing. Another way: send fake interest in a stock by rapidly changing the quoted price that investors see to determine if there is any interest in the stock - you have plenty of time to cancel the balance of an order before anyone from the outside can execute any real size against it. The list goes on and on. In Summary:
Electronic Trading brought down costs, High Frequency Trading brought down ethics.
How High Frequency Trading Harms Even Long Term Investors
Milliseconds, Microseconds and NanosecondsCapacity planning is based on peak rates. For the scenarios listed below, we will assume 1,000 symbols and 1 quote per time interval.
Trading at the Seconds Level
Rational human thought requires at least 1 second of time. In one second, a quote can reach everyone on Earth. A 1 Terabyte hard disk will store about 1.5 years of market data. Practically any Ethernet network is capable of receiving this information.
Trading at the Millisecond Level
Below one second, the realm of human perception teeters on the edge of rationality. A single blink of an eye takes 300-400ms. In one millisecond, a quote can travel 186 miles (300km). A 1 Terabyte hard disk will store about 2 days of market data. You will need a gigbit network to receive this information without delay. It takes the SEC a few months to investigate one days worth of data.
Trading at the Microsecond Level
In one millionth of a second, nothing a human does consciously, can be measured. A quote can travel about 1000 feet (300m). A 1 Terabyte hard disk will store about 10 seconds worth of market data, which means you need over 2,000 disks to store 1 day. To receive market pricing information, you would need a terabit network, which is currently a bleeding edge technology. You will be dead before the SEC finishes investigating an hours worth of data.
Trading at the Nanosecond Level
In one billionth of a second, light and therefore market data travels a mere 13 inches (30cm). That would require a new word similar to co-location, but meaning locating your machine inside another as in a blade-server. Just 1 second of market data would fill 100 Terabytes. Petabit networks don't yet exist outside of highly advanced labs. Humans will be living on another planet before the SEC finishes investigating an hours worth of data.
Trading at the Picosecond Level
You will be forever branded a sensationalist by the mere mention of picosecond (or nanosecond) trading, so try to resist.
Summary of Trading Speed Characteristics
1Not factored into this cost is the infrastructure needed to deliver the massive explosion of quote data that came with the arrival of HFT. It is this additional cost that raises the barrier to entry and thus narrows the diversity of market participants.
2Judging by the language in Reg NMS, regulators, and nearly all those who submitted public comments, were either unaware that the speed of light was limited, or that the limit was so high, that practically speaking, light (and thus information) traveled instantly from one location to another.