Volatility given on NSE quotes

I was calcualting my own historical volatility for NIFTY.

From the NIFTY quote the Annualized volatility is 47.29.

I am using a 50 day average - and downloaded 3+ years of data. My calculation comes around 23.7 - that is a big Difference.

So the question is- does anyone know the NSE India Calculation details- is it statistical or an Implied vol figure.

Regardless 47 % volatility for a Broad Market index is really amazing- I would think it would be in the 20's! Appreciate a debate on this.

Re: Volatiliy given on NSE quotes

Sorry I stand corrected ( please refer message above)

The NSE quote is around 33.85 for the volatility not 47.29. Still I am not able to account for nearly 10%. BTW I am using 365 days for annualization- it seems the NSE quote is doing the same- my guess would be that they are using some less than 50 day average- any comments?

Re: Volatiliy given on NSE quotes

hi
Did you get the answer to your thread ?
even I am also calculating historical volatility for nifty do you know the formula ?

HV(length) = sd(ln(close/yesterday's close),length)*100*square root(256)

where: length=length of volatility to be calculated(days)
ln = natural logarithm
sd = std dev