The typical rule of thumb is usually that it ought to be able to hold as much as four times as much as you anticipate it to be required to hold.

典型的经验法则是，通常认为它应该能够容纳多达四倍，你预计它是须持有。

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Robert Hazlett, pharmaceuticals analyst at Robertson Stephens, says he uses a rule of thumb that a drug is worth four times continuing sales.

FORBES: Magazine Article

Given the general volatility of thoroughbred racing, and the fact that the horses are, by rule, 3 years old, the favorite has only managed to win four times in the last 33 years (or 12% of the time, but who's counting).

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When Republicans use these types of rules four out of 10 times in a previous Congress and then vociferously object to the use of that rule now, I think that is -- I think that is -- again, the standard is to embrace something and then find it objectionable a pivot that requires something few figure skaters in the Olympics are able to pull off.

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