Variance is a measurement of the spread between numbers in a data set. Investors use the variance equation to evaluate a portfolio’s asset allocation.

Select-String is a cmdlet that is used to search text & the patterns in input strings & files. It is similar to grep on Linux & FINDSTR on Windows 11/10.

The churn rate is the percentage of subscribers who discontinue service subscriptions within a given time. Learn how to calculate customer churn rate.