The Dow staged a late day rally today, closing up 75 points to 10,750, despite the fact that oil prices have once again cracked through $50 per barrel. Many would expect that with oil at $51.39, stock prices would have suffered. After a 170-point Dow drop on Tuesday (oil soared more than $2 that day, to over $50), we have recouped most of those gains already without a pullback in the oil market.

From this, we see that the relationship between oil and stock prices can get pretty interesting. Many economists hate to see increasing energy prices, fearing it will cripple any moderate economic growth we do have in this country. They see higher gas prices at the pump as an indirect tax on consumers, curbing their disposable income. Since the consumer represents two-thirds of the U.S. economy, stock prices generally falter when gas prices head higher.

While I won't argue there is some connection, I have long thought that the impact higher energy prices have is somewhat exaggerated. After all, if the average consumer fills up his or her 15 gallon tank once a week, a 25 cent increase in the per-gallon price of gas costs that person about $195 per year extra. Hardly insignificant, but not enough to cripple an economy by any means, in my opinion.

Another interesting thing is how energy prices are affecting corporate earnings. While many will make the case that high gas prices will hurt the profit of consumer-related companies, earnings estimates have actually risen since the beginning of the year, even though oil prices have gone up as well. Growth in earnings for the S&P 500 was initially expected to be in the 7 to 8 percent range in 2005. Estimates have creeped up to between 9 and 10 percent already in the first two months of the new year. This has mostly been driven by the energy sector, whose profits are through the roof, and show no signs of slowing down.

As a result of higher profit estimates and a stock market that is down 1% thus far in 2005, the forward P/E on the S&P 500 has fallen to 16.2 or so. With the 10-year bond only yielding 4.29%, investors probably feel pretty comfortable buying stocks at these prices. The risk of course, is that energy prices fall meaningfully from here. The stock market might react postively to that initially, but don't forget that such a move will lower corporate profit estimates, leaving stocks relatively more expensive than they are now.