By Michael Wursthorn and Christopher Whittall 

Major U.S. stock indexes rose Tuesday as investors snapped up shares of technology and energy companies.

The Dow Jones Industrial Average gained 155 points, or 0.7%, to 21859 in recent trading. The S&P 500 added 0.8%, and the Nasdaq Composite rose 1.2%.

Meanwhile, investments considered to be relatively safe stores of value, including gold and U.S. Treasury bonds, retreated.

The broad upswing in U.S. stocks extended gains for the Dow industrials after the index suffered its biggest two-week decline of the year. Tensions between the U.S. and North Korea, as well as questions over whether the Trump administration can enact agenda items such as a tax overhaul, have weighed on stocks in recent weeks.

While the political climate continued to be a concern, investors said the strong earnings quarter, steady economic growth and slightly more attractive valuations following recent selloffs were driving markets.

"We're focusing less and less on the political backdrop," said Lew Piantedosi, director of growth equity for Eaton Vance. "It's the strength of the economy, not just here, but globally, that matter most to stocks. Earnings have been reasonably healthy for the last few quarters, too."

Shares of energy companies in the S&P 500 rose 0.7%, with Oneok and Cabot Oil & Gas posting some of the biggest advances.

Technology companies in the S&P 500 rose 1.3% on gains in shares of Seagate Technology and Micron Technology, among others.

Retailers were on the upswing, too. Shares of Macy's gained 4.9% after the company said it hired a senior eBay executive and streamlined its top management. Shoe retailer DSW rose 21% after it posted same-store sales growth for the first time in six quarters.

Investors are looking ahead to the Jackson Hole economic symposium later this week. The roster of top central bankers includes Federal Reserve Chairwoman Janet Yellen and European Central Bank President Mario Draghi, who will gather at the annual conference that kicks off Thursday.

Investors are watching for further details on the Fed's plans to scale back its balance sheet and clues on when the ECB could trim its asset purchases, which have helped underpin markets in recent years.

"We've been conditioned to expect something out of Jackson Hole each year," said Krishna Memani, OppenheimerFund's chief investment officer. "If there is a surprise, it'll come from [Mr.] Draghi."

Government bond prices edged lower, with the yield on the 10-year U.S. Treasury note rising to 2.210%, according to Tradeweb, from 2.182% on Monday. Yields rise as prices fall. Gold was down 0.4% to $1,291 a troy ounce.

The WSJ Dollar Index, which tracks the dollar against a basket of 16 currencies, rose 0.3% after declining slightly on Monday.

Stocks beyond the U.S. were mostly higher Tuesday. The Stoxx Europe 600 rose 0.8%, buoyed by gains in mining shares. Stock markets in the Asia-Pacific region mostly pushed higher, but the Nikkei Stock Average slipped less than 0.1%, notching its 11th decline in 13 trading sessions.

Ese Erheriene contributed to this article.

Write to Michael Wursthorn at Michael.Wursthorn@wsj.com and Christopher Whittall at christopher.whittall@wsj.com

(END) Dow Jones Newswires

August 22, 2017 13:28 ET (17:28 GMT)

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