Crude oil just broke $80.

In morning trade on Monday, the price of crude oil fell below $80 a barrel for the first time since mid-2012 as energy prices continue to plummet around the world.

The most recent drop in oil, which has been a bear market since topping out at about $107 during the summer, follows a cut in oil-price expectations from Goldman Sachs' Jeff Currie over the weekend.

Currie took his oil-price forecasts for WTI Crude to $75 a barrel in the first quarter of 2015 and to $70 a barrel in the second quarter of next year.

Longer-term, Currie expects WTI prices to stabilize near $80 a barrel, and Currie said that "uncertainty around the required price to slow down US shale production growth is a key risk to our forecast."

Currie's forecast relies on three key reasons:

We have greater confidence in the scale and sustainability of US shale oil production. This implies that the global cost curve has shifted lower and that cost deflation is sustainable.

We forecast that accelerating non-OPEC production growth outside North America will outpace demand growth, leaving the global oil market oversupplied.

We believe that OPEC will no longer act as the first-mover swing producer and that US shale oil output will be called upon to fill this role.

Here's the ugly chart of oil futures on Monday morning, which are off their worst levels but still below $80.

FinViz

And here's the long-term chart that shows the more than two-years it's been since oil was below $80.