The theory goes that commodity prices move in “supercycles” or bursts of phenomenal surges, followed by longer, less-exciting periods. As such, a barrel of oil at $50 is, well, normal. Many people think the oil price has crashed, but it has just gone back to its long-term historical trend, according to Ruchir Sharma at Morgan Stanley Investment Management Inc. That makes a barrel of oil at around $50 just about right based on a 100-year inflation-adjusted average, said Sharma, who manages $25 billion as head of emerging markets . “The price of oil is returning to normal in its long-term 100-year history,” Sharma said in an interview from New York . “We tend to have a short memory and we tend to forget that the price of oil breached the $50 a barrel level only a decade ago.” Brent crude oil futures, which trade in London and are used […]