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Chapter 10

Using Statistical Functions

In This Chapter
Calculating averages
Finding the maximum and minimum values
Counting the cells in a range of data
Using the Statistical functions offered by the Analysis ToolPak add-in

xcel includes one of the most complete sets of statistical functions available outside of
Ea dedicated statistics software program. These functions run the gamut from the more
mundane AVERAGE, MAX, and MIN functions to the more exotic and much more specialized
CHITEST, POISSON, and PERCENTILE statistical functions. In addition, the program offers an
assortment of counting functions that enable you to count the number of cells that contain
values, are nonblank (and thus contain entries of any kind), or count only the cells in a cell
range that meet the criteria you specify. In this chapter, you get a chance to practice work-
ing with the most commonly used statistical functions, AVERAGE, MAX, and MIN, as well as
the different counting functions.

Computing Averages

The average is the arithmetic mean computed by summing all the values to be averaged and
then dividing this total by the number of values. Excel’s AVERAGE function, which calculates
the average of a range or series of values, uses the following syntax:
AVERAGE(number1,[number2],[. . .])

One way to understand the workings of the AVERAGE function is to display the correspon-
ding SUM and COUNT formulas that return the exact same result. For example, suppose you
want to find the average of the values in the cell range D4:D8 in your spreadsheet by enter-
ing the following formula in a cell:

=AVERAGE(D4:D8)
In place of this AVERAGE function, you could obtain the same result by entering the follow-
ing formula:

=SUM(D4:D8)/COUNT(D4:D8)
Note that the COUNT function shown as the divisor in this equivalent formula returns the
number of cells in the specified range that contain numeric entries (see Exercise 10-3 later
in this chapter for practice on using COUNT).