JPMorgan Chase & Co. (JPM) , the largest U.S. bank, said first-quarter profit surged 35% as taxes decreased following President Donald Trump's cuts in the corporate rate, while bigger price swings in U.S. markets led to higher trading revenue. 

"The global economy continues to do well, and we remain optimistic about the positive impact of tax reform in the U.S. as business sentiment remains upbeat and consumers benefit from job and wage growth," JPMorgan CEO Jamie Dimon said in a  statement Friday announcing the results.

JPM said that income rose to $8.71 billion from $6.45 billion a year earlier. Adjusted earnings per share climbed to $2.37, beating the $2.27 average estimate of analysts in a survey by database provider FactSet. Still, JPMorgan stock was trading around 2% lower at $111.06 shortly before 11 a.m. ET.

Dimon has touted the benefits of Trump's tax cuts as providing tax relief for the middle class. But the new law, which the bank lobbied for, also delivered a windfall to its own bottom line; the company's income-tax expense declined by about $240 million, despite a $2 billion increase in pretax income, according to the statement. JPMorgan said it expects a tax rate this year of 20%, down from a 32% effective rate in 2017.

Investors are scrutinizing JPMorgan's earnings as an early indicator of how U.S. companies are faring as the $1.5 trillion of tax cuts -- intended to stimulate economic growth -- take effect, while businesses simultaneously must cope with higher borrowing costs imposed by the Federal Reserve.

Wall Street firms like JPMorgan are also benefiting from a resurgence in stock-market volatility as traders speculate over the pace of Federal Reserve interest-rate increases, U.S. trade tensions with China and the data-privacy scandal at Facebook Inc. (FB) . The CBOE Volatility Index, a key gauge of market volatility known as the "VIX," was 43% higher on average during the quarter.

Citigroup Inc. (C)  , a rival Wall Street bank, said in a separate report Friday that first-quarter profit jumped 13%, also fueled by growth in trading revenue. Meanwhile, San Francisco-based Wells Fargo & Co. (WFC) , struggling to recover from a series of regulatory penalties over allegedly aggressive sales practices, posted a 5.5% profit increase on a preliminary basis, noting that legal costs might have to be revised higher pending discussions with regulators over as much as $1 billion of new penalties related to auto insurance and mortgage-related violations. Bank of America Corp. (BAC) , Goldman Sachs Group Inc. (GS) and Morgan Stanley (MS) are all scheduled to post results next week.

The resurgence in market volatility has prodded investors out of last year's languor, when unusually calm markets kept investors on the sidelines and left few opportunities for traders at Wall Street banks to score gains on big price swings. 

JPMorgan's first-quarter stock-trading revenue surged by 26% to a record $2.02 billion, with strong performance in derivatives trading and hedge-fund financing, according to the press release. Revenue from fixed-income markets was $4.55 billion, up 8%, with strong results from foreign exchange, emerging markets and commodities offset by lower client activity in government-bond trading and corporate bonds.

The overall results also benefited from one-time accounting gains of $505 million, or 11 cents a share, Brian Kleinhanzl, an analyst at the brokerage firm Keefe, Bruyette & Woods, wrote in a report. Without the gains, JPMorgan would have reported earnings of $2.26 a share, missing analysts' average estimate, according to Kleinhanzl.

Gerard Cassidy, an analyst at RBC Capital Markets, said in a separate report that consumer-banking earnings were stronger than expected, while commercial-banking was slightly weaker.  Costs for bad loans totaled $1.17 billion, according to the press release, below Cassidy's estimate of $1.41 billion. 

JPMorgan Chase, Citigroup, Goldman Sachs and Facebook are holdings in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells the stocks? Learn more now.

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