MGM returns a Monthly geometric mean of a specified variable.  The value is placed on the last day of the month.

SYNTAX:

MGM(Cx, optional Time Increment)
where :
Cx is a conditional variable x
Time Increment Optional - specifies the source variables (Cx) Frequency when the Source Variable (CX) and target variable's (i.e. the variable being calculated) frequencies do not match.

NOTES:

The variable being averaged must be specified as a Conditional Variable (use "C" instead of "V")

The calculated value is listed on the last day of the month.

In all cases; blank, 0, and negative values are ignored in the calculation.

The result is stored based on target variables frequency:

• Daily - Last day of the month.
• Daily Detail - First slot on the last day of the month.
  

EXAMPLE 1: Returns the Monthly geometric mean from a variable

Source variable (71) is set to Daily and Target variable (106) is also set to Daily. Because both the Source and Target variables are the same (Daily), the time increment BYDAY will be used.

V106 = MGM(C71)

Variable 106 will contain the geometric mean of variable 71 on a monthly basis, having the value stored at the end of the month.

EXAMPLE 2: Return the Monthly geometric mean from an Hourly variable into a Daily Calculation.

Source variable (71) is set to Hourly and Target variable (106) is set to Daily.

V71 - Is a hourly parameter
V106 - Is a daily calculation

V106 = MGM(C71,BYHOUR)

Note: You MUST specify the Time Increment (BYHOUR) that matches the source variables frequency (IE the source variable V71 is Hourly, therefore we specify BYHOUR) in order for the function to return the correct value.

See: Working with Daily Detail Variables in Calculations.