10 things you need to know today (SPY, SOX, QQQ, DIA)

Yellen's Humphrey-Hawkins testimony continues. Federal Reserve Chair Janet Yellen will move her semiannual testimony to the Senate Banking Committee after appearing before the House Financial Services Committee on Wednesday.

Fed rate-hike odds are falling. The market sees just a 42.3% chance that the Fed hikes rates by the end of the year, according to Bloomberg's World Interest Rate Probability data. That's down from a 51.9% chance on Monday.

China's trade surplus swells. China's trade surplus grew to $42.77 billion in June as exports to the US and the EU grew by 19.9% and 15.2% from a year earlier.

The Bank of Korea lifts its growth forecast. The central bank held its benchmark interest rate unchanged at 1.25% and said it "forecasts a rate of GDP growth for this year higher than the April projection (2.6%)."

Ethereum is sliding. The cryptocurrency trades down by 6.5% at $208 an ether after falling by 25% from Monday to Tuesday before stabilizing on Wednesday.

Britain's financial regulator is paving the way to bring Saudi Aramco's IPO to London. The Financial Conduct Authority has proposed rules that would create a new category "within its premium listing regime" for sovereign-owned companies looking to go public.

Daimler slides following excess-emissions report. Shares of Daimler slid by 2.5% amid early trade in Frankfurt, Germany, after the German newspaper Sueddeutsche Zeitung reported that authorities were investigating the possibility the automaker used illegal software to manipulate emissions tests in Mercedes-Benz vehicles from 2008 to 2016, Reuters says.

Stock markets around the world are higher. Hong Kong's Hang Seng (+1.16%) hit a two-year high as it led the gains in Asia, and France's CAC (+0.57%) paces the advance in Europe. The S&P 500 is set to open up by 0.15% at 2,447.

Earnings reports trickle out. Delta Air Lines reports ahead of the opening bell.

US economic data remains light. Both initial claims and PPI will be released at 8:30 a.m. ET. The US 10-year yield is down by 1 basis point at 2.31%.