(Bloomberg) -- The Organization of Petroleum Exporting Countries cut its 2008 global oil demand forecast for a second time in three months as producers report difficulties selling ``heavy'' crude grades.
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A lack of investment in refinery units that make diesel has increased demand for light oils at the expense of heavy grades, OPEC said today.
The mismatch ``has left refiners with little option but to increase light grade throughputs, resulting in a widening spread between light and heavy crude,'' the report said.
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The price spread between Iranian heavy crude and West Texas Intermediate, the benchmark light crude in North America, has quadrupled to $10.99 a barrel, compared with a spread of $2.65 a barrel at the same time last year, according to Bloomberg data.
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