Oddly, the best hope for avoiding that 90-day wait could come from your cable company. HBO says it's in discussions with some cable, satellite and telephone providers that could sell access to HBO Now at launch, but nothing is set so far.
1 Use the Excel Formula =STDEV() and select the range of values which contain the data. 2  This calculates the sample standard deviation (n-1).3  Use the web Standard Deviation calculator and paste your data, one per line. Use the Excel Formula =STDEV() and select the range of values which contain the data. 2  This calculates the sample standard deviation (n-1).
Vice versa, variance is standard deviation squared. To calculate standard deviation from variance, only take the square root. In our example, the variance was 200, therefore standard deviation is 14.14. For calculating standard deviation of a data set, first calculate the variance and then find the square root.or sample variance and standard deviation, the only difference is in step 4, where we divide by the number of items less one. In our example we would divide 1,000 by 4 (5 less 1) and get the sample variance of 250. Sample standard deviation would be 15.81 (square root of 250).