Today the VIX went up 25% in one day!
Anyway, I am thinking what determines the value of the VIX?
I realize that mathematically it is the calculation of the implied volatility from the Black-Scholes equation, based on the price of SPY options, interest rate and dividends. But why...
...is it that when the S&P 500 goes down the VIX also usually goes up, but with no basic pattern. Sometimes it can go up 5% when the S&P 500 goes up 2%, but other times it can go up 10% or more.
So why??????

Anyway, I am thinking what determines the value of the VIX?
I realize that mathematically it is the calculation of the implied volatility from the Black-Scholes equation, based on the price of SPY options, interest rate and dividends. But why...
...is it that when the S&P 500 goes down the VIX also usually goes up, but with no basic pattern. Sometimes it can go up 5% when the S&P 500 goes up 2%, but other times it can go up 10% or more.
So why??????
Sweet, sweet money