A slump in oil below $50 a barrel—a level it has held above for most of the past decade—has raised the prospect of a new era of lower prices, although a return to super-cheap oil seems unlikely.
Prices below $50 for the two crude oil benchmarks, North Sea Brent and U.S. West Texas Intermediate, were the norm prior to 2005. Brent averaged just $18.37 a barrel in the 1990s, WTI $19.70 a barrel, and both only broke above $50 for the first time in late 2004.
China's explosive economic growth over the past decade, coupled with flatlining global output, saw Brent soar above $140 in 2008 and it has spent more than 90 percent of the past decade above the $50 mark.
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But producers globally, in particular U.S. shale drillers, are now pumping record amounts of oil just as China's growth looks set to steady at lower levels, while alternative energy sources and better efficiency are denting demand in the developed world.