Energy states have tried to diversify. Wyoming and Alaska remain highly reliant on oil revenue.

During 2014, oil prices dropped by half. Except more of the same in 2015.

A lousy crop means high prices. At least for the real thing.

Oil, whose price has halved in the past year, accounts for 95 percent of the country’s exports and 45 percent of the government’s budget.

After first oil well was drilled in 1892, derricks became a symbol of Los Angeles.

The price of oil is dropping. Good news or bad news?

Maybe we should be asking what isn't made from a barrel of oil.

Kai talks with Adrian DeLeon, the mayor of Carrizo Springs, Texas.

If oil prices fall, will tires cost less? The answers are far from black and white.

Kai Ryssdal talks to commercial grain farmer Curt Mowery.