Big changes on the way for the Dow industrials

Paul Taggart | Bloomberg | Getty Images

The Dow Jones industrial average is getting a new look, with one of Wall Street's oldest names getting added to the mix.

While the Dow tinkers with its 30 components periodically, often with only modest fanfare, this one will be noticed.

Gone are Alcoa, the company that traditionally kicks off earnings season, along with Bank of America, which is the second-largest financial institution in the U.S., and Hewlett-Packard, which has been in the blue chip index for 16 years.

In their place will be Goldman Sachs, Nike and Visa.

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The changes take effect after the close of trading Sept. 20 and mark the first new names in two years.

The moves will cause alterations to the way the index is weighted.

Visa and Goldman Sachs will have the second- and third-highest respective weightings, according to Bespoke Investment Group.

"By definition then, the Dow is going to look and act very differently going forward," said Dan Greenhaus, chief market strategist at BTIG. "Leaving aside NKE/HPQ, you've replaced two stocks that essentially don't matter in AA and BAC with two that do."

Also, the divisor Dow Jones uses to calculate the index will change to the point where a $1 move in any stock will move the index 6.5 points, compared with the previous 7.7 points.

Along with being a target for Wall Street critics, Goldman brings heft to the index both in reputation and share value.

Stock price, in fact, is what drove the three-for-three move, the most ambitious change for the index since 2004.

"We have made some big steps in terms of improving the index," David Blitzer, managing director and chairman of the Index Committee at S&P Dow Jones Indices, told CNBC. The Dow is "price-weighted, and very low-priced stocks have very little impact."

The three stocks leaving had an average price of $15 while the new ones average $134.50.

Timing, though, was at least a little curious.

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BofA was the top Dow 30 gainer in 2012, surging 109 percent, and has added another 25 percent in 2013.

The two others to leave the index have fared poorly, though.

Hewlett-Packard, long a rumored target for a Dow exit, tumbled 45 percent last year, though it has jumped 57 percent in 2013.

Alcoa is the Dow's worst performer this year, losing nearly 7 percent.

Goldman is up 25 percent in 2013, while Visa has gained about 18 percent and Nike is up more than 30 percent.

—By CNBC's Jeff Cox. Follow him @JeffCoxCNBCcom on Twitter.