VIX in plain English

Bill Luby at Vix and more explains in plain English what VIX readings mean in terms of daily moves.
http://vixandmore.blogspot.com/2010/05/rule-of-16-and-vix-of-40.html link
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Using the rule of 16 and the 1/3 trading days time frame, the following translations should be committed to memory:

* VIX of 16 – 1/3 of the time the SPX will have a daily change of at least 1%
* VIX of 32 – 1/3 of the time the SPX will have a daily change of at least 2%
* VIX of 48 – 1/3 of the time the SPX will have a daily change of at least 3%

Simple math allows us to do a linear interpolation. Today, with the VIX hovering around 40, options traders are expecting that the SPX will have daily change of 2.5% about 1/3 of the time.

Looking backward, as volatile as the market have been recently, only three days out of the past month have resulted in daily changes of 2.5% or more. In fact, for all of 2010, there have been only four days in which the SPX has been either up or down at least 2.5%.
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Long BRKB, GLD, SPY, TLT