U.S. oil futures on Friday settled below $41 a barrel for the first time since the Great Recession to suffer an eighth straight weekly loss—the longest streak of weekly losses since 1986. Prices sank to intraday lows under $40 after data from Baker Hughes showed that the number of active U.S. oil drilling rigs rose 2 to 674 as of Aug. 21.

Weaker-than-expected Chinese manufacturing data and a plunge in the U.S. stock market spurred worries about the outlook for energy demand. West Texas Intermediate crude for October delivery fell 87 cents, or 2.1%, to settle at $40.45 on the New York Mercantile Exchange. The October contract, which become the front month at Thursday’s settlement, posted a weekly decline of 6.2%. Based on the most-active contracts, futures prices marked their lowest settlement since March 2, 2009 and saw weekly loss of 4.8%, their eighth weekly decline in a row. Nymex prices haven’t seen a streak of that many weekly losses since the 10-week stretch of losses that ended on March 7, 1986, according to FactSet data.

The string of losses for WTI crude has sparked increasing comparisons with the major bear market in 1986, said Tim Evans, an energy analyst at Citi Futures, in a note. “The key takeaway from both the 1986 and 1999 bear market cycles…is that it took a change in OPEC policy to help the market reverse the slide,” said Evans. In 1999, it actually “took more than one round of cuts in order to fully rebalance the market.”

But output from the Organization of the Petroleum Exporting Countries was at roughly 31.5 million barrels a day during July, he said. “It looks like the market will remain in a supply/demand surplus at least through 2016.” 

October Brent crude on London’s ICE Futures exchange lost $1.16, or 2.5%, to $45.46 a barrel—more than 7% lower on the week. Prices for Brent gained last week after six weeks of declines.

Several analysts have argued that the oil-price slide is likely overdone, with market sentiment souring when prices were already low due to oversupply concerns. WTI prices have slumped over 14% month to date.

In the Atlantic, Hurricane Danny was headed toward the Caribbean. But James Williams, energy economist at WTRG Econmoics, said that even if a hurricane was to cause all Gulf of Mexico oil production to go offline, “the world would still be over supplied by at least a half million barrels and day—and this is before the additional oil to come from Iran.”

Gasoline prices turned higher on Nymex following news of a fire at a refinery in Delaware.