By Caitlin Ostroff and Karen Langley

U.S. stock indexes hit fresh records Thursday, with the Dow Jones Industrial Average closing above 34000 for the first time.

Strong earnings reports and improving economic data pushed the Dow up 0.9%, to about 34035 in 4 p.m. trading. The S&P 500 gained 1.1%, with both indexes setting record closing highs.

The technology-heavy Nasdaq Composite advanced 1.3% as shares of big tech stocks rallied.

A powerful rally has pushed stocks to repeated highs in 2021, and many investors believe the rollout of Covid-19 vaccines and plentiful government spending suggest shares have room to keep rising. The S&P 500 and Dow are both up about 11% for the year.

Investors will monitor earnings reports in the coming weeks as they assess how the outlook for corporate earnings aligns with increasingly high stock prices. Analysts expect that earnings among companies in the S&P 500 jumped 29% in the first quarter from the same period a year earlier, according to FactSet.

"There's elevated expectations coming into this quarter, but we still think that there's going to be a significant amount of companies beating those estimates," said Chad Oviatt, director of investment management at Huntington Private Bank.

On Thursday investors rewarded shares of several reporting companies. BlackRock shares gained 1.9% after the asset manager said its quarterly profit rose nearly 50%. UnitedHealth Group shares climbed 3.6% after the healthcare services company posted a larger profit and stronger revenue on the year in the first quarter.

Shares of Bank of America, by contrast, dropped 3.6% after the lender reported a jump in expenses.

Money managers also parsed new data as they look for signs of improvement in the economy. U.S. retail sales -- a measure of purchases at stores, at restaurants and online -- jumped 9.8% last month. Household incomes have benefited from recent fiscal stimulus measures that saw $1,400 checks hit some Americans' bank accounts.

"Economic data is going to continue to get better and better and better as the economy opens up," said Tom Mantione, managing director at UBS Private Wealth Management.

Fresh data also showed that 576,000 Americans applied for first-time unemployment benefits in the week ended April 10, a decrease from the 769,000 who applied in the week prior. The Federal Reserve has said employment is one of the factors it is watching to determine when to eventually lift interest rates.

An anticipated economic recovery has led some investors to buy shares of companies sensitive to a rebound, such as energy, travel and banks, which has helped send indexes to repeated record highs this year.

"We want to see that the 2021 numbers -- even the 2022 numbers -- are going to continue to look good," said Esty Dwek, head of global market strategy at Natixis Investment Solutions. "We want to see what guidance is going to be. For a lot of 2020, we had no guidance."

Among individual stocks, newly listed cryptocurrency exchange Coinbase rose 1.4% to $333. Shares rose as high as $429.54 during the stock's trading debut Wednesday and ended the session at $328.28.

Overseas, the Stoxx Europe 600 gauge added 0.5%. The Shanghai Composite Index declined 0.5%, and Hong Kong's Hang Seng Index edged 0.4% lower. South Korea's Kospi added 0.4%.

In bond markets, the yield on the 10-year U.S. Treasury note dropped to 1.548%, from 1.637% Wednesday.

Write to Caitlin Ostroff at caitlin.ostroff@wsj.com and Karen Langley at karen.langley@wsj.com

(END) Dow Jones Newswires

April 15, 2021 16:26 ET (20:26 GMT)

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