The Commodities Correlation Conundrum

Earlier this month, while suggesting that Fools not go overboard with energy equities, I voiced my concern that oil and the stock market were becoming uncomfortably correlated. This suggested to me that price signals were breaking down, and that poor capital allocation decisions would be made as a result.

My comments on correlation were based on simple observation of day-to-day market behavior, and I didn't have any hard numbers for you. Bloomberg has since performed a study that confirms my hunch.

Based on percentage changes over a trailing 60-day period, correlations between the S&P 500 and the Reuters/Jefferies CRB Index (a basket of various commodities) hit a high of 0.74 this month. That's the tightest correlation seen in at least 50 years. The correlation between stocks and crude oil alone also topped 0.7 (or 70% in percentage terms).

It made a good bit of sense for assets of all sorts to move in tandem when the market tanked. From ordinary investors to executives at companies like Chesapeake Energy (NYSE: CHK  ) and Denbury Resources (NYSE: DNR  ) to overleveraged hedge funds, margin calls forced many folks to sell whatever wasn't nailed down. Even gold -- both the futures and the SPDR Gold Shares (NYSE: GLD  ) ETF -- took a nosedive back in October. While the markets were plenty rattled about fundamentals at the time, this was as much a liquidity event as anything else.

The recent pile-on in equities, commodities, and emerging markets -- through both individual securities and exchange-traded funds like the U.S. Natural Gas Fund (NYSE: UNG  ) and the iShares MSCI Emerging Markets (NYSE: EEM  ) ETF -- shows an almost comparable lack of discrimination, save for an apparent appetite for junk stocks over quality.

While the indiscriminate selling was forced to some degree, nothing's compelling today's purchases, other than perhaps a desperation to claw back some of 2008's massive losses. From an institutional money manager's point of view, perhaps the only thing worse than losing half your clients' money would be to do so and then sit out the ensuing rally. You'd lose even more of your assets under management, and maybe even your job.

In gambling, the attempt to win back losses is called "chasing." There's more than a bit of that happening in the markets today, and it makes this Fool extremely uneasy.