The entire gains of the S&P over the last year were finally wiped out today
Most shares came tumbling, as did oil, particularly when Crude oil droped $1 in a few minutes at about 10:30am ET. Oil started selling off pretty badly.
Other industries affected were Tech and Services but Financial seems to be holding it's own as I write.
Nevertheless. Even with the selloff, if you invested in the Energy sector on Jan 1st you'd still be up about 50% right now - if you were in a diverse basket of the S&P you'd be at less than 0%.
I see that crude is rallying slightly now. I expect a Bull rally in energy sometime in the next few days. You'll know when it's due because crude oil will rise for about 3 days in a row.