#EXCEL TRENDLINE FORMULA PLUS#

The formula is the intercept in F2 plus the slope in E2 times this row's month number. In column D, enter a formula to calculate the predicted sales trendline. Excel returns both the slope and the y-intercept. After you type the closing parenthesis, press Ctrl+Shift+Enter.

Select two cells that are side by side.It turns out that Excel really wants to return two numbers from the function. The first time you do this, you might wonder how the number 204.81 could describe a line. Entering the formula the wrong way returns a single answer of 204.8133. If you select a single cell and enter =LINEST(C2:C35), it will return a single number, which is of no help. Instead of returning one number, it actually returns two (or more) numbers as the result. This is just my wild guess Excel can calculate the number exactly. In this case, the value for b would be 10,000, and the value for m would be 400. If you were to look at the data, you might guess that the prediction for a given month is $10,000 + Month number x $400. In this example, y is the revenue for the month, m is the slope of the line, x is the month number, and b is the y-intercept. You might remember from math class that a trendline is represented by this formula: y = mx + b Excel offers a function called LINEST that will calculate the formula for the trendline. Strategy: You can use the least-squares method to fit the sales data to a trendline.

The Trend function uses the least squares method to find the line of best fit and then uses this to calculate the new y-values for the provided new x-values.Problem: I have monthly historical sales data. The Excel Trend function will find the line of best fit for any set of values provided to it. Note that, it is not essential that the supplied points fit exactly along the straight line y = 2x + 10, (although they do in this example). The known x- and y-values are stored in cells A2-B5 of the spreadsheet, and are also shown in the spreadsheet graph.

#EXCEL TRENDLINE FORMULA SERIES#

In the spreadsheet below, the Excel Trend Function is used to extend a series of x- and y-values that lie on the straight line y = 2x + 10. Trend Function Examples Example 1 - Extension of a Simple Straight Line

Type your function into the first cell of the range, and press CTRL-SHIFT-Enter.See the Excel Array Formulas page for further details. To input an array formula, you need to first highlight the range of cells for the function result. Therefore, the function must be entered as an Array Formula (see the examples below). If more than one new y-value is to be calculated by the Excel Trend function, the new values will be returned as an array. If is FALSE the constant b is set to 0 and the straight line equation becomes y = mx. If is TRUE (or if this argument is omitted) the constant b is treated normally ДЄn optional logical argument that specifes whether the constant 'b', in the straight-line equation y = mx + b, should be forced to be equal to zero. If the argument is omitted, it is set to be equal to the. ДЄn optional argument, providing one or more arrays of numeric values representing a set of new x-values, for which you want to calculate the corresponding new y-values.Д®ach array of should correspond to an array of. If omitted, the set of takes on the value. This is an optional argument which, if provided, should have the same length as the set of known_y's. Where the function arguments are as follows: known_y's

Excel trendline formula