The Average( ) function returns the average of a set of values. Null values inside the set will be ignored. You may pass up to 27 arguments into the function.
x1, x2, x3,... must be of numeric type.
Average(Column('This Rating'),Column('Last Rating'))
The average of the columns This Rating and Last Rating will be returned.
Average(12, .NULL., 24)
18 will be returned by the above function. .NULL. is ignored.
Average(12, 0, 24)
12 will be returned by the above function.