Hi Trainer,

I'm trying to get the Historical Volatility over 3 years in a monthly Timeframe, but not sure whether the following formula ist correct. The Output should be a simple decimal value:

SQR(ABS((SUM(LOG(C / C1) ^ 2,36) - LOG(C / C36) ^ 2/36) / 36))

Thanks!!

To get the historical volatility, you need to multiply what you have by 100 and the square root of the number of periods in a year.

100 * SQR(12) * ABS((SUM(LOG(C / C1) ^ 2, 36) - LOG(C / Cx) ^ 2 / 36) / 36) ^ .5

The 1600 at the beginning of the regular historical volatility formula is a result of using 256 as the number of trading days in a year (mostly because the square root is a nice even 16).

Thanks!

You're welcome.