Oil keeps falling. And falling. How low can it go?

The price of oil keeps falling. And falling. And falling. It has to stop somewhere, right?

Even after trending down for a year and a half, U.S. crude has fallen another 17 percent since the start of the year and is now probing depths not seen since 2003.

"All you can do is forecast direction, and the direction of price is still down," says Larry Goldstein of the Energy Policy Research Foundation, who predicted a decline in oil in 2014.

As oil plunges, energy companies cut jobs, postpone projects

The world's biggest oil companies are slashing jobs and backing off major investments as the price of crude falls to new lows — and there may be more pain to come.

Companies like BP, which said Tuesday it is cutting 4,000 jobs, are slimming down to cope with the slump in oil, whose price has plummeted to its lowest level in 12 years and is not expected to recover significantly for months, possibly years. California-based Chevron said last fall that it would eliminate 7,000 jobs, while rival Shell announced 6,500 layoffs.