Excel 2000 in a Nutshell

Name

TREND

Synopsis

Use TREND to find the values that fit the specified linear trend using the method of least squares. This function returns an array of values that indicate the predicted y-axis values. The function determines the values based upon the equation y=mx + b.

To Calculate

=TREND(Known_Y's, Known_X's, New_X's, Const)

The Known_Y's argument is required for this function. All other arguments are optional.

Known_Y's

This array must contain a series of positive numbers. If the values in the array are in a single column, then the function interprets the values in each column of the Known_X's as a separate variable. If the values in the array are in a single row, then the function interprets the values in each row of the Known_X's array as a separate variable.

Known_X's

If this argument is omitted, it is assumed to be an array of values in the range of {1,2,3,...} that is the same size as the array specified by the Known_Y's argument.

New_X's

Indicates the new x-axis values for which you want to find the corresponding y values. If these values are omitted, they are assumed to be the same as the Known_X's argument.

Example

Figure 15-47 illustrates how to use TREND to determine the future y-axis values based upon the known values for the x-axis, y-axis, and future x-axis values. Remember, this is an array function, so you need to use Ctrl+Shift+Enter to add the function to all cells in the array.

Figure 15-47. Use TREND to determine the future y-axis values based upon the linear trend ...