Most services charge a fee for historical volatility, which to me seems a bit goofy since it is a really straight forward operation. The following is the HV calculation in case you are interested:
1) Return
, where Pt is close price on day t.
2) Average day-to-day changes over n-day period can be calculated as sum of returns divided on the number of days: 
3) Daily historical volatility is calculated on the basis of n days is estimated as
4) Annualized Historical Volatility is calculated as HV=HVdaily*sqrt(252)
Additionally, the five-month chart of VIX futures that I wrote about on Saturday does update dynamically so you can check that at any time on the same page. I think it's probably too valuable to just give away so this may change in the future.
4) Annualized Historical Volatility is calculated as HV=HVdaily*sqrt(252)
Additionally, the five-month chart of VIX futures that I wrote about on Saturday does update dynamically so you can check that at any time on the same page. I think it's probably too valuable to just give away so this may change in the future.
