By his calculation, cats kill approximately 50 million birds each year in Germany alone.

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Hence David Cameron's calculation that any obfuscation by his government would be counter-productive.

BBC: Independence referendum: triumphalism deferred

Especially if his calculation that the public are with him is shared by his opponents.

BBC: Analysis

And so General Musharraf's calculation is that he can burnish his credentials as an anti-terrorist fighter by ending this in a violent manner.

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