Time to kick off another week.

Citigroup's Earnings

Real Money Stock of the Day Citigroup (C - Get Report) posted better-than-expected results for the first quarter as a steep cut in the U.S. bank's effective corporate tax rate helped to offset a fall in stock-trading revenue, wrote TheStreet's Bradley Keoun. 

Net income climbed by 2% from a year earlier to $4.71 billion, the New York-based bank said Monday in a press release. Earnings per share were $1.87, beating Wall Street analysts' average estimate of $1.80.

The effective tax rate for the quarter dropped to 21% from 24% in the first quarter of 2018.

Goldman Sachs Earnings

Goldman Sachs (GS - Get Report) said first-quarter profit fell less than expected, as fees from advising on mergers and acquisitions helped to mitigate an abysmal performance from the Wall Street bank's juggernaut trading business, wrote Keoun.

Net income fell by 21% from a year earlier to $2.25 billion, the New York-based bank said Monday in a press release. Earnings per share were $5.71, beating Wall Street analysts' average estimate of $4.89.

Investment-banking fees climbed 1% from a year earlier to $1.81 billion, though revenue from trading bonds, commodities and currencies declined by 11% to $1.84 billion, and stock-trading revenue tumbled 24% to $1.77 billion.

Huawei's Potential 5G Chip Sales to Apple

China's Huawei Technologies said it was open to the idea of selling cutting-edge 5G chips to Apple (AAPL - Get Report) , according to a report from CNBC. 

Huawei, which is the world's largest manufacturer of networking gadgets, is a leader in 5G or so-called fifth generation smartphone technology, wrote TheStreet's Simon Constable.

"We are open to Apple in this regard," said Huawei founder and CEO Ren Zhengfei, in an interview with CNBC.

An agreement with Apple would mark a major change in strategy as in the past Huawei has used its chips solely in its own-brand smartphones, according to CNBC. The news also likely would be seen as a challenge to chipmakers Intel (INTL - Get Report) and Qualcomm (QCOM - Get Report) .

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