6. Diamond Offshore Drilling ( DO) shares have plunged 33% this year. The company was hurt by the ban on offshore drilling in the wake of the BP ( BP) oil spill in the Gulf of Mexico. Its third-quarter profit tumbled 45% to $199 million, or $1.43 a share, as revenue dropped 12% to $800 million. Its operating margin narrowed from 53% to 36%. The company's management expects a prolonged slowdown in the Gulf region, but has relocated most of its rigs to international locations. Outlook: With oil prices above $80 a barrel and rising, Diamond is forecasting solid business growth. But researchers have a cautious outlook for its stock. Of those covering Diamond, seven advise purchasing its shares, 13 recommend holding and 15 advocate selling. A median target of $68.92 indicates that Diamond is marginally undervalued. However, the stock sells at a 55% discount to oil and gas industry averages, trading at 9.8 times its 12-month earnings projections.