There is a nice bit of commodities markets context — especially useful for thinking about oil markets — at the tail end of a Bloomberg article on the collapse this year (down 34%) in the price of sugar.
Between 1970 and 2000, rallies in commodities markets lasted about three years, with prices rising 45 percent, said John Normand, global currency and fixed income strategist at JPMorgan Chase & Co. Slumps would last the same period of time, with prices falling 42 percent. The current rally has lasted 51 months with prices rising 171 percent, he said.
Oil was, until recently, a one-decision commodity and there are a lot of people reluctant to let go of that view of something that has made them a great deal of money. There is, however, a growing number of people looking at some fairly pain-inducing prices for oil and gold, like the $60/$550 target from Logic Advisors (cited in the same Bloomberg piece).