Feb 10, 2012 (Bloomberg) -- Aluminum traders probably closed out bets that prices will climb as the number of outstanding contracts declined to the lowest in more than three months at the same time as prices fell.
Open interest in London Metal Exchange aluminum futures declined by 9,457 lots to 1.35 million contracts in the week ended Feb. 8, the lowest level since Oct. 19, according to LME figures. Each lot represents 25 metric tons of the metal used in cars or packaging. The benchmark contract for three-month delivery fell 0.5 percent in the period.
When open interest and prices fall together, this suggests investors liquidated bets on climbing prices, according to Macquarie Group Ltd. Open interest in LME aluminum has fallen 15 percent since reaching an all-time high of almost 1.6 million lots in December.