A simple way to try to determine a range min / max within which it is expected that the prices will vary for a particular financial instrument is to correlate the price, volatility and time duration projection.
I then tried to develop this 'confidence interval' for some indices (especially those for which there is a volatility index regularly listed on the CBOE).
the result is a work in progress, in the sense that the back test was conducted on a very limited number of samples (nearly closures Monthly, 2009):
S & P 500 (ending August 2009 1020.68)
minimum: 944 maximum
: 1096
DOW JONES (ending August 2009 9496)
minimum: 8855 maximum
: 10,137
NASDAQ (Closing August 2009 2009.76)
minimum: 1852 maximum
: 2166
STOXX 50 (2412.02 closing in August 2009)
minimum: 2210 maximum
: 2613
