I think it has to do with oil futures. The speculators, who basically buy quantities of oil in let's say, Feb. or Mar. hold on to it 'til the price rises enough hopefully, for them, and then they sell it to make a profit. The trend has been going up constantly for months, which is why it goes up periodically, even when oil prices are starting to drop. The price is based on what happened days or weeks ago, unless a crisis arises. It was announced today that they are under investigation for possibly illegally and artificially driving the price up. That may have something to do with the price going down some. They might have gotten wind that the investigation was imminent (sp.) Correct me if I'm way out of line. Also, this is a very simplistic example.
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