Do you know how I would calculate the SD (or any function) on a series of data held in a table?
To know the formula of standard deviation, once go through the following links. It may be helpful for you.
http://www.easycalculation.com/statistics/learn-standard-deviation.php
http://www.mathmotivation.com/symbolic/standard-deviation.html
http://www.codecogs.com/d-ox/stats/moments/standard_deviation.php