Wales wing Shane Williams also offers cover in the position, but a lengthy stay at number nine is unlikely to find favour with player, country or region.

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In utilizing the short interest data, one can look for a large percentage increase in the number of shares sold short, or the short interest ratio, which tells the number of trading days that would be needed to cover the short position.

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The revenue from the short sale can help cover the cost of the long position, making the pairs trade inexpensive to put on.

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