Excel Function : COVARIANCE.S
Returns the sample covariance, the average of the products deviations for each data point pair in two data sets
Microsoft Excel Reference Page
Syntax and Description of the COVARIANCE.S Excel Function
Covariance is a measure of how two variables change together. It is used to determine how likely it is for an event to happen.
About COVARIANCE.S Excel Function
COVARIANCE.S is an Excel function that returns the sample covariance of two supplied sets of values. The function is used to assess the relationship between two variables.