X sample mean. X Mean of the data. The formula takes the absolute value of the difference between a value and the mean and divides it by the number of values.
N Number of data points.
It is called Assumed mean method. The following formula is used to calculate a percent deviation. Standard deviation is a mathematical term and most students find the formula complicated therefore today we are here going to give you stepwise guide of how to calculate the standard deviation and other factors related to standard deviation in this article. Then the deviation of the data points from this value is calculated.