File this article under “one more reason you should be a long-term investor”:

In the time it takes the average American to read this paragraph, the average stock will have been purchased, and then sold. The average holding period for a stock, according to a prominent economist and college professor who studies the market, is now 22 seconds, roughly the time it takes the average person to read about 90 words. That means in the four or five minutes someone dedicates to this article, some market sharpy will make 15 trades.

Other tidbits:

High frequency trading is estimated to account for as much as 70% of the trades on Wall Street.

That 22-second holding period is actually an improvement. In 2009, the average holding period was 20 seconds.

And, finally, this quote from an analyst at Morningstar, which is the big old silver lining to all of this madness:

…”In a way, it may well be that the shorter-term focus means greater opportunities for those with a longer-term focus. If all of the money is trying to extract every last penny from short-term news, that may well mean that there is time-period arbitrage by focusing on the long-term, recognizing that you are not going to day-trade in a manner superior to that of the hedge funds. You’re trying to figure out who the winners will be five or 10 years out, and that’s a different matter, one that the hedge funds could not care less about, which means that it’s a much safer place for the average investor to be.”

And when you put “time-period arbitrage” into the stock market de-jargonator machine, it comes out as:

“Less trading, more fishing.”

So there you have it.