The global supply glut in the oil market is even bigger than expected and could push prices to as low as $20 a barrel, Goldman Sachs warned in a report on Friday.

Over the past two months, crude oil CLV25, has plunged from around $60 a barrel to below $40 a barrel at one point, underscoring the weak fundamentals in the energy markets, analysts at the investment bank said. Brent UK:LCOV5 futures have slumped from around $65 in June to below $50 in recent days.

“In fact, the oil market is even more oversupplied than we had expected and we now forecast this surplus to persist in 2016 on further [Organization of the Petroleum Exporting Countries] production growth, resilient non-OPEC supply and slowing demand growth, with risks skewed to even weaker demand given China’s slowdown and its negative [emerging-market] feedback loop,” the analysts including Damien Courvalin and Jeffrey Currie said.

The downbeat assessment of the 2016 supply landscape led the Goldman analysts to cut their already bearish price forecast again: they now expect West Texas Intermediate crude oil to average $45 a barrel next year, down from $57 expected previously. And the forecasts for the next few months are even bleaker as laid out in the table below.

Forecast horizon New outlook Old outlook One month $38 $45 Three months $42 $49 Six months $40 $54 12 months $45 $60

For Brent, the bank cut its 2016 forecast to $49.50 a barrel from $62 expected previously, citing Iran’s potential to ramp up production in 2016 as well as surprisingly high OPEC supply.

To clear the oversupply, oil prices will need to stay lower for longer in order to force production cuts, the analysts argued.

“While not our base case, the potential for oil prices to fall to such levels, which we estimate near $20 a barrel, is becoming greater as storage continues to fill,” they said in the report.

In that vein, the International Energy Agency said in a report on Friday that the recent oil-price slump could force the U.S. and other non-OPEC countries to cut production next year by the most since the early 1990s.

Goldman also noted it expects U.S. production to fall “sufficiently to start rebalancing the market”, which should help oil prices find a bottom over the next six to nine months.

“We would expect equities to bottom with commodity prices,” the analysts said, raising their coverage view on the European integrated oil companies to neutral from cautious.