Why the Dow Closed at an All-Time High, Again

Wednesday saw a second straight day of all-time record closes for the Dow Jones Industrial Average , as 2013's remarkable bull run continues. Today's gains brought the Dow's year-to-date returns to 16.3% -- not bad considering we're not even halfway through the year. The Dow ended up 48 points, or 0.3%, to end at 15,105.

With more than two-thirds of the index's components ending in the black, shares of UnitedHealth Group led all advancers, gaining 3.3%. The nation's largest for-profit health insurer rallied after the Obama administration released an unprecedented breakdown of costs for certain procedures at different hospitals across the country. The data, which compare rates at more than 3,000 hospitals, show wide-ranging differences in what hospitals charge for the same procedures. UnitedHealth shareholders seem to think this tactic will be effective in bringing down medical costs -- and the company's payouts.

With all 30 blue-chip components trading higher this year, Hewlett-Packard shares have posted the largest percentage gains. Stubbornly continuing their rise, shares ticked up 2.8% today. HP has shown some signs of a turnaround, but the $8.8 billion writedown it took last year on the acquisition of information management company Autonomy and a record decrease in worldwide PC sales to begin 2013 suggest that there are still some concerns.

Aluminum giant Alcoa also traded higher Wednesday, advancing 2.7%. While some materials, gold in particular, have seen dramatically falling prices in recent months, materials as a sector outperformed all other sectors today, boasting 1.1% gains. Apart from it just being a good day for materials, there wasn't much else rallying the stock.

Turning to the handful of losers in the index, McDonald's was the largest decliner, slipping 1.3% as head-to-head competition with other fast-food rivals intensifies. Today brought news that Mickey D's U.S. sales rose in April -- a pleasant surprise. But with slow growth domestically, the fact that international revenue is struggling doesn't bode well for the iconic company.

The article Why the Dow Closed at an All-Time High, Again originally appeared on Fool.com.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.The Motley Fool recommends and owns shares of McDonald's. It recommends UnitedHealth Group. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.

Copyright © 1995 - 2013 The Motley Fool, LLC. All rights reserved. The Motley Fool has a disclosure policy.