“The stock market today is a war zone, where algobots fight each other over pennies, millions of times a second,” Salmon writes in his recent column for Reuters and BuzzFeed. It’s an especially timely point in the wake of the Knight Capita fiasco.
Salmon’s point is based on this animated image, which shows the amount of high-frequency trading in the stock market between January 2007 and January 2012:
Notice how the total activity balloons as it gets closer to the present? To Salmon, this is a cause for great alarm.
“The stock market is clearly more dangerous than it was in 2007, with much greater tail risk,” he writes. “Meanwhile, in return for facing that danger, society as a whole has received precious little utility.”
In particular, Salmon questions the value that this increased activity has created. “Are spreads a tiny bit tighter than they might be otherwise?” he asks. “Perhaps, but that has no effect on stock-market returns for long-term or even medium-term investors.”
So why should the profits of a few speculators be defended when these activities provide no real benefit to society? They shouldn’t, Salmon suggests. Not anymore. His answer? A financial transaction tax – a solution Salmon himself opposed back in 2007.
The reason for his change of heart is simple.
“The potential cost [of high-frequency trading] is huge; the short-term benefits are minuscule,” Salmon writes. “Let’s give HFT the funeral it deserves.”