The GEOMEAN() function returns the geometric mean of a set of positive data values. The syntax for the function is GEOMEAN (number 1 , number 2, ....number_n). The arguments for the function "number 1, number 2..number_n" can be a series of up to 30 values, an array, a referenced range of cells or a named range. Logical values will also be accepted when entered directly into the function however referenced cells that do not contain values or that cannot be converted to numeric values such as text, logical values or empty cells will be ignored. The GEOMEAN function calculates the nth root of the product of all the numbers in a set of n data values. For example: GEOMEAN(3,2,4,5,) = 3.30975092 as when the numbers 3,2,4,5 are multiplied to make 120 and then the 4th root is found giving 3.30975092. The result represents a measure of the average factors of a distribution of numbers. When the numbers in the dostribution are all the same the geometric mean is the sam as the arithmetic mean. e.g. GEOMEAN(10,10,10,10) = 10. as 10x10x10x10 = 10,000 and the 4th root of 10,000 is 10. In the arithmetic mean 10+10+10+10 =40 and 40/4 =10 yeilding the same result. To learn more about the uses of the geometric mean see [The Geometric Mean Mathematics Knoledgebase].

How to use the GEOMEAN() function: Type " =GEOMEAN( " Enter the coordinate of the first data cell "A2" Type a colon. Enter the coordinate of the last data cell "A7" Type ")" then press the "Enter" key.

Note: All arguments for the GEOMEAN function must be positive otherwise the function will return a #NUM! error value to the cell. This is due to the fact that Excel cannot directly evalute the square roots of negative numbers (even if in some cases two neagtive factors will still give a positve product to be rooted Excel will n ot accept the argument).