Colas reports that the ten most heavily weighted names in the index—IBM, Chevron, 3M, McDonald's, Caterpillar, UnitedTechnologies, ExxonMobil, Travelers, Boeing and P&G—are responsible for 543 points (or 57 percent) of the total 950 point advance for 2013.
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As Colas notes, this is large part due to the price-weighted nature of the Dow. Bigger stock price equals bigger weighting. Market caps, unlike in the S&P 500 or Nasdaq indexes, mean nothing in the Dow.
The top contributor is IBM, up 4.8 percent on the year and adding 70 Dow points. Only three Dow stocks are down on the year: Alcoa (-1.8 percent), Bank of America (-3.3 percent) and UnitedHealth (-1.5 percent). Their drag on the Dow was a total of 9.4 points.
Despite this year's surge, the Dow's ten most heavily weighted names still look relatively attractive. Based on analysts' earnings expectations for 2013, these stocks trade for 13.3 times earnings and 12.4 times next year's numbers.
"You always have to take these estimates with a large grain of salt, to be sure," Colas tells his clients. "But 12 to 13 times forward numbers is no one's idea of an 'expensive' market."
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