Greece teeters on default; SpaceX explosion; Airbnb's whopping valuation

Wall Street kicking off the holiday-shortened week with a selloff.

Stocks are tumbling across the board with all three major indexes down sharply (^GSPC) (^DJI) (^IXIC)  in early trading as the risk of the Greek default grows after Greece failed to strike a deal with its creditors over the weekend.  Athens has closed banks and the stock market, and imposed capital controls.

The Greek ETF -- Global X FTSE Greece 20 ETF (GREK) which tracks the performance of the 20 largest securities listed on the Athens Stock Exchange (SAGD.AT) is taking a big hit this morning. 

Greece is not the only country reaching a tipping point. Puerto Rico Governor Alejnadro Garcia Padilla told the New York Times the commonwealth is not able to repay its $72 billion in debt and that the island will likely seek concessions from its creditors, including up to five years of deferred payments.

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Macy's (M) shares are lower this morning. Deutsche Bank downgraded the department store chain to "sell" from "buy". The firm says it does not have confidence the retailer could break out of its same-store sales rut.

General Electric (GE) shares also slipping in early trading.  The industrial conglomerate took another major step in shedding its banking businesses. The company is selling its GE Capital operations that provide commercial car and truck financing in the U.S., Mexico, Australia and New Zealand for about $7 billion in cash to Canada's Element Financial.  Meantime, Paris-based Arval has entered into a memorandum of understanding to purchase GE Capital's European fleet operations.

Apollo Education (APOL) shares are also in focus this morning. The owner of the University of Phoenix and other for-profit colleges is set to report results after the close of trading today.  Analysts are looking for Apollo to earn $0.47 a share. That's down sharply from $0.76 per share the company earned a year ago. Revenue is expected to fall more than 12% to about $698 million.

Airbnb's BIG valuation 

Airbnb just completed one of the largest funding rounds ever. The home-sharing company reportedly raised $1.5 billion, giving them a $25.5 billion valuation.

Elon Musk's company Space-X suffered a major setback when its Falcon 9 rocket exploded shortly after launch on Sunday. The unmanned rocket was carrying two tons of goods for astronauts at the International Space Station. Space-X has launched  a joint investigation with the Federal Aviation Administration.

AIIB launches 

The China-backed Asian Infrastructure Investment Bank launched today. Delegates from 57 countries gathered in Beijing to sign an agreement determining each member's share in the development bank.