Calculating the standard deviation and T-Value against that data set results in a realistic range against the historic data.

Calculating standard deviation manually can be time-consuming and complex. Excel's STDEV formula can automatically calculate the standard deviation of any set of numbers, so you don't have to go ...

Pooled standard deviation is a useful tool when analyzing data sets. It is especially helpful when you’ve taken the time to properly weigh your standard deviations so everything is in balance.