The answer is--this goes way back-- it's an old tradition and they used to have to do this by hand.

答案要追溯到很久之前,这是个古老的传统,他们过去用手工计算

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And so this time when you hand it back, this value, I store it in -- we'll say X, and now we actually have retained the value.

这次当你拿回这个值时，我把它存储在X中，现在我们把这个值保存了。

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