I wrote a spread sheet so I could look at a glance and get a price range. This combined with technical analysis is how I SHOULD make my trades. I always start out this way, but I get side tracked.

This spreadsheet helps bring back a little reality to my decision making. If I am thinking about a target price, and I see that it is 2 standard dev’s away, I probably would not take the trade.

The spreadsheet is written for Gnumeric, which is more accurate than Excel. And free. And runs on Linux.

Standard Deviation Spreadsheet

You plug the volatility, price and date into the spreadsheet, and it will calculate the price ranges to 1, 1.5 and 2 standard deviations.