Portugal's borrowing costs rose sharply Wednesday as it sold almost one and a half billion dollars in short-term securities.

VOA: special.2011.04.08

When they created margin rules that the seller had to be borrowing against securities. Just made more money when securities went up more value.

当我们发明保证金制度,卖空证券时需要交担保金,证券升值时能赚到更多钱。

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