LONDON (Bloomberg) Bermuda-based Frontline Ltd, the world’s biggest operator of supertankers, slumped to a seven-year low in Oslo trading as the company said its ships operated at a loss in the first quarter and the next three months may be no different.The shares fell as much as 4.5 percent to 100.7 kroner, the lowest compared with intraday prices since May 2004, and were at that price as of 10.30 a.m. local time. The stock plunged 33 percent this year, valuing the company at 7.86 billion kroner ($1.41 billion).Frontline said first-quarter net income fell 81 percent to $15.5 million, or 20 cents a share, better than the loss of $572,000 anticipated by the median of 10 analysts’ estimates compiled by Bloomberg. The “weak trend” of the quarter will probably extend into the next period and the company may sell vessels, Frontline said in a statement on its website yesterday.“They are retaining all the cash they can,” said Erik Nikolai Stavseth, an analyst at Arctic Securities ASA in Oslo, who has a “sell” recommendation on the shares. “They are basically saying ‘we are going to sit down and try to weather the storm’.”Returns on supertankers that reached $177,036 a day in July 2008 were last at $8,900, according to the London-based Baltic Exchange, which publishes daily rates for more than 50 maritime routes. Frontline needs $29,700 to break even on its vessels. The surge in rates in 2007 and 2008 spurred owners to order more ships, on the eve of the worst global recession since World War II. Those vessels are now leaving shipyards, swelling the tanker fleet faster than demand.Oil tankers may be unprofitable for five more years before a glut that caused a 95 percent slump in returns since 2008 is eroded, Tor Olav Troeim, an alternate director at Frontline, told a conference in Oslo yesterday.Oil-tanker owners have responded to the slump in rates by cutting their speeds from an average of 10.8 knots in July 2008 to 8.8 knots now, according to ship-tracking data compiled by Bloomberg. There are more than 600 tankers anchored globally, up from about 350 three years ago, the data show.The glut will take time to erode because only 10 percent of the fleet is more than 15 years old, reducing the speed of demolitions, Troeim said in an interview after his speech in Oslo. By contrast, a quarter of the dry bulk fleet hauling coal and iron ore is more than 20 years old, he said. The slump in dry bulk shipping may be over in three years, Troeim said.Frontline earned an average of $28,600 a day for each of its very large crude carriers in the first quarter, down from $45,300 a year earlier, according to a presentation on the company’s website. Returns on smaller suezmaxes averaged $17,300, compared with $31,800 a year earlier. The break-even rate for suezmaxes is $24,700, Frontline said.