Here is what you need to know.

Yellen takes her testimony to the House. Fed Chair Janet Yellen will appear before the House Financial Services Committee on Wednesday for the second day of her semiannual Humphrey-Hawkins testimony. In her prepared remarks on Tuesday, Yellen noted that waiting too long to raise interest rates is ‘unwise’ and could cause a recession.

UK employment is at its highest point on record. The UK added 37,000 jobs in the three months to December as it posted a sixth consecutive quarterly gain. The British pound is down 0.3% at 1.2428 versus the dollar.

Humana is pulling out of Obamacare. Humana, one of the five largest publicly traded health insurers, announced on Tuesday that it will abandon individual marketplaces in 2018 because it is “seeing further signs of an unbalanced risk pool.”

Cigna is suing Anthem after walking away from their merger. Cigna has filed a $13 billion lawsuit against Anthem for “the lost premium value to Cigna’s shareholders caused by Anthem’s willful breaches of the Merger Agreement.” Anthem responded by saying the terms of the agreement do not allow Cigna to back out of the merger and that it intends to follow through on the deal.

Toshiba tumbles after announcing its massive writedown. Toshiba fell more than 10% at its open in Tokyo following the company's announcement that it was taking a $6.3 billion writedown on its US nuclear unit, Reuters reports. The stock would trim some of its losses of the course of the session to finish down 7.6%.

Warren Buffett is loading up on airlines. A 13-F filing released on Tuesday showed the legendary investor bought more than $5 billion worth of airlines as he initiated a new position in Southwest Airlines while adding to his stakes in Delta Air Lines and American Airlines. Buffett slashed his stake in Walmart by 89%.

Twitter's CEO is buying stock. Jack Dorsey scooped up $7 million worth of Twitter shares in the wake of the company's disappointing fourth-quarter earnings that pushed the stock down 10%.

Stock markets around the world are higher. Hong Kong's Hang Seng (+1.2%) was the top performer in Asia and France's CAC (+0.5%) is out front in Europe. The S&P 500 is set to open little changed near 2,338.

Earnings reports keep coming. Pepsi and Groupon are among the companies reporting ahead of the opening bell while Cisco and Kraft Heinz highlight the names releasing their quarterly results after markets close.

US economic data is heavy. Empire Manufacturing, CPI, and retail sales will all be released at 8:30 a.m. ET before industrial production and capacity utilization cross the wires at 9:15 a.m. ET and the NAHB Housing Market Index is announced at 10 a.m. ET. The US 10-year yield is higher by 1 basis point at 2.48%.