August 24, 2006 Economic Scene/New York TIMES The Rapidly Changing Signs at the Gas Station Show Markets at Work
By HAL R. VARIAN THE recent gyrations in oil prices offer a textbook illustration of how financial markets and commodity markets interact. Oil prices are notoriously volatile, particularly when times are tense in oil-producing countries — just about all the time these days. So when BP announced this month that it might have to suspend as much as 8 percent of the nation's oil production because of corrosion in pipes on the North Slope of Alaska, the price of crude oil immediately shot up by 3 percent and wholesale gasoline prices simultaneously increased by about 2 percent. But why? Even if it will cost more to produce gasoline in the future, gasoline being sold today was made with cheaper oil. This must be a rip-off, right? Actually, no. The reason behind the quick price change is a phenomenon known as storage arbitrage. [or "speculation" or "hoarding"; academic economists like Varian love obscure jargon! -- JD] To spell out the argument, imagine that you own a storage tank full of gasoline that is currently worth $2 a gallon at wholesale prices. It is widely believed, however, that the price of gasoline will be $2.10 next week. You would be crazy to sell your gasoline now: just wait a few days and the higher price will be yours. But if everyone waits a few days, there is no gasoline to be sold now and the resulting shortage pushes the price of gasoline up. How high does it have to go? The answer is $2.10 a gallon [or rather, slightly less, because selling gasoline now rather than later rewards one with interest on the revenues]. That is the price necessary to induce those who have gasoline to sell it now rather than to wait till next week. This argument does not depend on whether you think the gasoline market is a paragon of perfect competition or an evil oligopoly. [I thought economists knew nowadays that perfect competition can be "evil."] All it requires is that you believe that people who own gasoline, like just about everybody with something to sell, prefer to receive a higher price rather than a lower price. Even if the price of gasoline were set by a perfectly benevolent conservationist, we would expect to see the same pattern of price movements. If oil will be scarcer in the future because of the BP pipeline shutdown, we would want to conserve [or hoard] the already-produced gasoline that we have now. That means that the price of gasoline has to rise right away to prevent hoarding and to encourage conservation. Storage arbitrage arguments were featured in a recent article in the Sunday Business section of The New York Times with the headline "Is a Futures Stampede Keeping Oil Prices High?" The article described a provocative report written by Ben P. Dell, an analyst at Sanford C. Bernstein & Company, that blamed speculation [i.e., "storange arbitrage"] in oil futures markets for high oil prices. Mr. Dell's argument was that inexperienced institutional investors had been investing in contracts for future delivery of oil, driving up futures prices. If the price of oil to be delivered in the future goes up, it has to pull the current spot price up as well. [Varian's real argument is with the "inexperienced institutional investors" bit, not the speculation bit, since "storage arbitrage" is a form of speculation.] There is no risk [sic! -- no asset holding is totally risk-free except perhaps US T-bills] associated with holding the oil in storage since owners can sell futures contracts, collecting a payment now to deliver the oil later. If you don't happen to have a tank of oil in your backyard, that is not a problem: just go out and buy some on the market. The article pointed out that on Aug. 4 it was possible to "buy heating oil in New York Harbor at $2 a gallon and store it and sell a future to deliver it in December for $2.24." Perhaps Mr. Dell is right that speculation in the oil futures market is driving up spot prices. But we should not expect that to be the normal situation. As long ago as 1953, Milton Friedman argued that speculation normally helps to stabilize prices rather than destabilize them. [and what assumptions did he make? why should we believe him? speculative bubbles _never_ happen?] Mr. Friedman's argument was applied to currency trading, but the same [unsupported] reasoning works here. If speculative trading tends to push prices higher when they are already high and lower when they are already low, then traders must be buying high and selling low. That would mean that traders have to lose money on average — which does not seem very likely. [why not? it happened to the US stock market circa 2000. Paper gains in wealth need not be realized.] To the contrary, speculative traders try to buy low and sell high, activities that by their nature tend to push prices up when they are too low and down when they are too high. Since Mr. Friedman's 1953 article several papers have been published, both supporting and attacking this argument. But the general principle seems quite robust. Mr. Dell's report specifically cited the rush of new and inexperienced traders into commodities markets as the cause of the current problems. Mr. Friedman's argument was a long-run argument: speculators who bought high and sold low would be driven out of business. [it's also an argument based on an ahistorical view of the world, with no path-dependence and no fundamental uncertainty. In any event, after the inexperienced losers are driven out of the market, new ones enter, so that there will be a new supply of losers. Further, there's no reason why there can't be innocent by-standers driven out of the market because they're not liquid enough (rather than because they bet wrong). So the bubble's burst can lead to downward over-shooting. ] But there is no reason speculators cannot lose money in the short run, particularly if they are inexperienced. Mr. Dell says that storage facilities are now close to capacity, which will make it more difficult to play the arbitrage game in the future. Indeed, crude oil prices have declined nearly 8 percent in the last two weeks. [we can't make _any_ conclusions from a mere two-week trend. That's a pretty basic mistake, Hal.] If speculators start to worry that the price of oil could soon be significantly lower, some of that stored oil would come back on the market, pushing spot prices down, and offering welcome relief to consumers. Hal R. Varian is a professor of business, economics and information management at the University of California, Berkeley. -- Jim Devine / "Segui il tuo corso, e lascia dir le genti." (Go your own way and let people talk.) -- Karl, paraphrasing Dante.
