The TREND function is a Statistical function in Excel. This article will show you how to use Excelâ€™s TREND function with 3 examples.
Introduction to The TREND Function
The TREND function calculates the values of a given set of X and Y and returns additional Yvalues by using the least square method based on a new set of Xvalues along with a linear trend line.
 Syntax
=TREND(known_y’s, [known_x’s], [new_x’s], [const])
 Arguments Description
Argument  Required/ Optional  Description 

known_y’s  Required  A set of dependent yvalues that is already known from the relationship of y = mx + b. Here,

known_x’s  Optional  One or more sets of independent xvalues that is already known from the relationship of y = mx + b.

new_x’s  Optional  One or more sets of new xvalues for which the TREND function calculates the corresponding yvalues.

const  Optional  A logical value specifying how the constant value b from the equation of y = mx + b should be calculated.

 Return Value
Calculated Yvalues along with a linear trend line.
Using TREND Function in Excel: 3 Examples
In this section, we will show you how to utilize the TREND function to calculate certain values based on given values in Excel.
1. Calculating GPA from Exam Score with The TREND Function
In this section, we will learn how to estimate GPA for a new dataset based on previously given data. Consider the following example, where we will return the Predicted GPA of the New Score in the right table based on the Exam Score and GPA given in the left table.
Steps:
 Pick a cell to store the result (in our case, it is cell F5).
 In the cell, write the following formula,
=TREND($C$5:$C$13,$B$5:$B$13,E5)
Here,
$C$5:$C$13 = known_y’s, dependent yvalues.
$B$5:$B$13 = known_x’s, independent xvalues.
E5 = new_x’s, new xvalues to calculate the TREND value for.
 Press Enter.
You will get the estimated GPA for the new score you stored in your dataset based on a given set of arrays.
2. Predicting Future Value with TREND Function
Here, we will predict future sales based on occurred monthly sales value.
Look at the following data. We have sales value from Jan20 to Sep20, and with the TREND function, we will predict the sales from Oct20 to Dec20.
Steps:
 Pick a cell to store the result (in our case, it is cell F5).
 In the cell, write the following formula,
=TREND($C$5:$C$13,$B$5:$B$13,$E$5:$E$7,TRUE)
Here,
$C$5:$C$13 = known_y’s, dependent yvalues.
$B$5:$B$13 = known_x’s, independent xvalues.
$E$5:$E$7 = new_x’s, new set of xvalues to calculate the TREND value for.
TRUEÂ = logical valueÂ to calculate normally.
 Press Enter.
You will get the predicted sales value of all the upcoming months that you provided in the formula at once.
3. Utilizing Excelâ€™s TREND Function for Multiple Sets of XValues
Until now, we have learned how to utilize the TREND function only with one xvalue. But this time, we will learn how to calculate TREND if there are multiple xvalues.
Look at the following dataset. Here, we have more than one xvalues (Buyers and Other Cost in the first table). We also want to calculate the Estimated Sales based on two different xvalues (New Buyers and New Cost in the right table).
Steps:
 Pick a cell to store the result (in our case, it is cell I5).
 In the cell, write the following formula,
=TREND($E$5:$E$13,$C$5:$D$13,$G$5:$H$7)
Here,
$E$5:$E$13 = known_y’s, dependent yvalues.
$C$5:$D$13 = known_x’s, multiple sets of independent xvalues.
$G$5:$H$7 = new_x’s, new set of multiple xvalues to calculate the TREND value for.
 Press Enter.
You will get the estimated sales value based on multiple xvalues that you provided in the formula at once.
Things to Remember
 The known values â€“ known_xâ€™s, known_yâ€™s â€“ need to be linear data. Otherwise, the predicted values could be inaccurate.
 When the given values of X, Y, and new X are nonnumeric, and when the const argument is not a Boolean value (TRUE or FALSE), then the TREND function throws #VALUE! error.
 If the known X and Y values are different lengths, then the TREND function returns #REF error.
Download Workbook
You can download the free practice Excel workbook from here.
Conclusion
This article explained in detail how to use the TREND function in Excel with 3 examples. I hope this article has been very beneficial to you. Feel free to ask if you have any questions regarding the topic.
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