Microsoft Office Tutorials and References

In Depth Information

**Syntax**

would be better if you could perform the regression once and have Excel cal-

culate all the values from that regression. The TREND function helps you

do this.

Syntax

=TREND(known_y's,known_x's,new_x's,const)

The TREND function returns values along a linear trend. It fits a straight

line (using the least-squares method) to the arrays known_y's and

known_x's. It returns the y values along that line for the array of new_x's

that you specify.

The TREND function takes the following arguments:

•
known_y's

known_y's
—
This is the set of y values you already know in the re-

lationship y = mx + b. If the array known_y'sis in a single column,

each column of known_x'sis interpreted as a separate variable. If

the array known_y'sis in a single row, each row of known_x'sis in-

terpreted as a separate variable.

•
known_x's

known_x's
—
This is an optional set of x values that you might

already know in the relationship y = mx + b. The array known_x'scan

include one or more sets of variables. If only one variable is used,

known_y'sand known_x'scan be ranges of any shape, as long as they

have equal dimensions. If more than one variable is used, known_y's

must be a vector (that is, a range with a height of one row or a width of

one column). If known_x'sis omitted, it is assumed to be the array

{1,2,3,...} that is the same size as known_y's.

•
new_x's

new_x's
—
These are new x values for which you want TREND to re-

turn corresponding y values. new_x'smust include a column (or row)

for each independent variable, just as known_x'sdoes. So, if

known_y'sis in a single column, known_x'sand new_x'smust have the

same number of columns. If known_y'sis in a single row, known_x's

and new_x'smust have the same number of rows. If you omit new_x's, it

is assumed to be the same as known_x's. If you omit both known_x's

and new_x's, they are assumed to be the array {1,2,3,...} that is the

same size as known_y's.

•
const

const
—
This is a logical value that specifies whether to force the

constant b to equal 0. If constis TRUE or omitted, b is calculated nor-