Datasheet

Part I: Putting the Fun in Functions

Using Functions in Formulas

Functions are like little utility programs that do a single thing. For example,

the SUM function sums up numbers, the COUNT function counts, and the

AVERAGE function calculates an average.

There are functions to handle many different needs: working with numbers,

working with text, working with dates and times, working with finance, and

so on. Functions can be combined and nested (one goes inside another).

Functions return a value, and this value can be combined with the results of

another function or formula. The possibilities are nearly endless.

But functions do not exist on their own. They are always a part of a formula.

Now that can mean that the formula is made up completely of the function or

that the formula combines the function with other functions, data, operators,

or references. But functions must follow the formula golden rule: Start with

the equal sign. Look at some examples:

Function/Formula Result

=SUM(A1:A5)

Returns the sum of the values in the

range A1:A5. This is an example of a

function serving as the whole formula.

=SUM(A1:A5) /B5

Returns the sum of the values in the

range A1:A5 divided by the value in

cell B5. This is an example of mixing a

function’s result with other data.

=SUM(A1:A5) + AVERAGE(B1:B5)

Returns the sum of the range A1:A5

added with the average of the range

B1:B5. This is an example of a formula

that combines the result of two

functions.

Ready to write your first formula with a function in it? This function creates

an average:

1. Enter some numbers in a column’s cells.

2. Click an empty cell where you want to see the result.

3. Enter =AVERAGE( to start the function.

Note: Excel presents a list of functions that have the same spelling as the

function name you type. The more letters you type, the shorter the list

becomes. The advantage is, for example, typing the letter A, using the ↓

to select the AVERAGE function, and then pressing the Tab key.

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