Before the bell:

U.S. stocks were set to drop at Friday's open, extending a loss from the previous session, as news of a massive earthquake and tsunami in Japan added to concerns over conflict in North Africa and the Middle East.
An 8.9-magnitude earthquake hit northern Japan on Friday, triggering tsunamis and sending a massive wave filled with debris that included boats and houses inching toward land. The death toll was more than 59, according to the Kyodo News Agency.
U.S. markets fell sharply Thursday, as economic data both domestically and abroad put a damper on investor sentiment. Investors' moods were darkened further by more reports of unrest in the Middle East, specifically news reports that Saudi Arabian police fired shots on anti-government protestors.
World markets:

Companies: The Japanese disaster had an impact on stateside insurance companies such as Aflac (AFL), which experienced a premarket stock drop of 3%. Three-quarters of Aflac's revenue come from Japan.
Economy: Retail sales rose 1% in February, matching expectations. Excluding automobile sales, retail sales rose 0.7%, only slightly higher than the projected increase of 0.6%.
Two economic reports are due out after the opening bell. The University of Michigan releases its March consumer sentiment survey at 14:55 GMT and the Commerce Department issues its January business inventories report shortly afterwards.
Economists, on average, are looking for the University of Michigan survey to come in at a reading of 76.5, down from 77.5 in February. Business inventories are expected to have risen 0.8%.
Oil for April delivery fell $2.76 to $99.94 a barrel
Gold futures for April delivery rose $1.20 to $1,413.70 an ounce, recovering from an earlier slump.
The price on the benchmark 10-year U.S. Treasury dropped, pushing the yield up to nearly 3.39% from 3.37% late Thursday.