In terms of share-price performance, Utah's largest publicly held companies managed to nose out the Dow Jones industrial average in the race for best return on investment during the first six months of 2011.

The Salt Lake Tribune/Bloomberg Index, which tracks the share prices of the 27 largest public companies that are either headquartered in Utah or have strong ties to the state, was up 7.6 percent from the closing bell on Dec. 31, 2010, through the end of trading on June 30.

During that same turbulent period, the 30 well-known companies that make up the Dow industrials gained 7.2 percent. The S&P 500 was up just 5 percent.

"We saw a lot of volatility in the market during the first half, but it turned out to be uninspiring," said Dave Russon, president of Investment Management Consultants in Salt Lake City. "And it depends upon whether you want gauge the market's performance by looking at the Dow or the S&P 500. They both were up single digits."

Even with the ups and downs, the Utah index had some stellar performers.

Dynatronics Corp., a Salt Lake City-based company that makes medical equipment used by physical therapists, chiropractors and sports medicine practitioners, remained the state's best-performing stock during the first half, maintaining the position it held during the first quarter. Its shares closed on June 30 at $1.46, up 132 percent so far this year.

The best-performing Dow stock was American Express, which has operations in the Salt Lake Valley and was up 20 percent during the first half of 2011. National Semiconductor was tops on the S&P 500, up 79 percent in the first six months.

Kelvyn H. Cullimore Jr., Dynatronic's president, said the company earlier this year signed contracts with three group-purchasing organizations that will make the company's products available to tens of thousands of clinics and hospitals.

"Our new contracts with those GPOs continue to drive interest in our company," he said. "We've even had interest from some institutional investors for the first time."

Utah's Zagg Inc., which sells protective film coverings to keep electronic devices scratch-and-dent free, was the second-best performer, with shares up 76 percent.

Zagg recently reported that its net income for the first quarter of its 2011 fiscal year was $3.3 million, or 13 cents per share, a 312 percent increase over the same period a year ago. It also announced that it had purchased Logan-based iFrogz Inc., in a transaction worth $105 million. The latter, which will be operated as a wholly owned Zagg subsidiary, produces protective cases, headphones and earbuds for smartphones, electronic tablets and other mobile devices.

Merit Medical Systems, a South Jordan-based maker of disposable medical products and a frequent presence among Utah's top 10 companies, finished the first half of 2011 with the fifth-best performing stock. Its shares were up 42 percent.

Last month, Merit sold 5.5 million shares in a secondary offering of its stock, raising $87.6 million. The company plans to use the proceeds to repay $25 million in debt, expand its manufacturing facilities and for potential strategic acquisitions.

Not all of the companies on the Tribune/Bloomberg Index managed to have gains.

Some of the best-known companies in the state saw their shares decline, with Overstock.com off 8 percent and EnergySolutions down 11 percent.

Shares of the Park City Group, which was just added to the Russell Microcap Index, were off 13 percent. The company, a software service provider that helps retailers and their wholesalers manage their supply chains, said Tuesday that it had reduced its outstanding debt balance by 20 percent.

"As our growth accelerates in the coming quarters, so will cash-flow generation, which we will use to further reduce debt and strengthen our balance sheet," CEO Randall K. Fields said in announcing the plan.

The stock of Headwaters Inc., the South Jordan-based building products company, fell 32 percent because of continuing weakness in the nation's construction industry. It was Utah's worst-performing stock during the first half.

steve@sltrib.com

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