There's no end to the savage slide in global oil prices, which is taking a huge toll on the local energy sector, while Metcash slumps on a poor earnings and the dollar plumbs new four-year lows. Oil prices are continuing to slide , with US crude falling more than $US2 to a five-year low today, while Brent futures have touched a fresh four-year low, extending a steep sell-off after OPEC decided not to cut production last week , keeping markets well supplied.