The year is 1996. You are Alan Greenspan and you are in the bathtub watching an episode of Frasier

You are head of the federal reserve and the stock market is booming. Your favourite boybands are touring the world. Life is good. The Nasdaq has just climbed to 1300.

But that is just too high. All this internet talk. It's too risky. Too much too soon. It's irrational. It cannot last. It will lead to a long bear market. It's... exuberant. We need to intervene. Then, eureka! the phrase comes to you "irrational exuberance". That's it! It's going in tomorrow's speech.

The Nasdaq would go on to quadruple in the next three and half years to over 5000.

Of course, by 2002, the Nasdaq would fall to 1150. But that's less than 15% down from the point of irrational exuberance. It would hit 5000 again in 2015.

True story.