The MEAN function returns a numeric value that is the arithmetic mean (average) of its arguments. The type of this function is numeric.
Usage
FUNCTION MEAN ({argument-1} ... )
Parameters
Argument-1 must be class numeric.
Returned Values
1. The returned value is the arithmetic mean of the argument-1 series.
2. The returned value is defined as the sum of the argument-1 series divided by the number of occurrences referenced by argument-1.