Here are five things you must know for Tuesday, May 15:  

1. -- Stock Futures Lower Ahead of U.S.-China Trade Talks 

U.S. stock futures were pointing lower on Tuesday, May 15, as investors awaited the next round of trade talks between the U.S. and China to begin in Washington.

Contracts tied to the Dow Jones Industrial Average  declined 53 points, those linked to the broader S&P 500  fell 3.25 points, and Nasdaq futures were down 12.25 points.

With the Dow riding an eight-session winning streak, investors might be tempted to book profits Tuesday after the U.S. dollar index, a measure of the greenback's strength against a basket of six global currencies, jumped to 92.75 - the highest level since Dec. 28 - following a sustained move over 3% for the yield on the 10-year U.S. Treasury.

The second round of trade talks between the U.S. and China begins Tuesday with the two sides still "very far apart" on key issues such as intellectual property protections and agricultural tariffs, according to Terry Branstad, the U.S. ambassador to China.

The U.S. economic calendar on Tuesday includes Retail Sales for April at 8:30 a.m. ET, and the Empire State Manufacturing Survey for May at 8:30 a.m.

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2. -- Home Depot Reports Earnings

Home Depot Inc. (HD)  posted stronger-than-expected first-quarter earnings but said same-store sales were hit by the colder winter temperatures that also have impacted activity in the key spring period.

Home Depot said earnings for the three months ended in April were $2.08 a share, topping the Wall Street consensus of $2.05. Revenue rose 4.4% to $24.9 billion, narrowly missing the consensus forecast of $25.16 billion as same-store sales grew 4.2%. The Atlanta-based retailer also confirmed full-year sales guidance of 6.7% growth and a comparable same-store sales growth rate of 5%.

"We are pleased by the strength of our business despite a slow start to the spring selling season," said CEO Craig Menear. "Outside of our seasonal business, we had solid results in all markets and categories and are seeing strong momentum in all lines of business during these first few weeks of May."

"These trends, as well as a favorable housing and macroeconomic backdrop, give us confidence to reaffirm our sales and earnings guidance for fiscal 2018," he added.

Home Depot fell 2.2% in premarket trading on Tuesday.

3. -- Seattle Passes 'Head Tax' That Was Opposed by Amazon

Amazon.com Inc. (AMZN) and Starbucks Corp. (SBUX) , two of Seattle's largest businesses, will have to pay a new tax to help fund homeless services and affordable housing under a measure approved by the city.

The City Council unanimously passed a plan Monday that taxes businesses making at least $20 million in gross revenue about $275 per full-time worker each year - lower than the $500 per worker initially proposed, the Associated Press reported. The so-called head tax would raise roughly $48 million a year to build new affordable housing units and provide emergency homeless services.

Action Alerts PLUS holding Amazon - Seattle's largest private sector employer - publicly opposed the measure, as did more than 130 other businesses.

4. -- China Blue Chips Set for MSCI Debut

China's biggest blue-chip stocks will be added to benchmarks pegged to more than $1.6 trillion in investment funds next month, index provider MSCI said, in a move that is likely to ignite renewed interest in equities in the world's second-largest economy.

MSCI will add the stocks of 234 China-based companies to its closely watched Emerging Market Index on June 1, using a two-step process that is expected to be completed by September. The move means the yuan-denominated stocks, known as "A shares," will initially comprise around 0.39% of the Emerging Market Index, a figure that could drive between $20 billion and $300 billion in new share purchases as investors seek to replicate the benchmark in the coming years.

5. -- Vodafone CEO Colao to Step Down

Vodafone Group PLC (VOD) CEO Vittorio Colao will step down in October after 10 years at the world's second-largest mobile operator.

Colao will be replaced by Chief Financial Officer Nick Read on Oct. 1.

The announcement of Colao's departure follows last week's news that Vodafone reached a deal to buy for about $22 billion Liberty Global's (LBTYA) cable TV and broadband networks in Germany and Eastern Europe.