From a native Spanish speaker,

PEMEX PRODUCTION STAYS IN A NOSEDIVE

In Spanish Spanish, at least, "En picado" is the way airplanes fall when they stall.

http://www.spanishdict.com/AS.cfm?e=picado

Nice. Certainly seems to fit the facts as described in the article. But isn't the gender wrong? Not the first word to flip gender between the Old World and the New World, of course.

Thanks for the translation. You too, Plucky.