By: Damien Mazzone

There are a couple of simple changes that could help automate this approach. Since you’re focussing on linear regression (and there’s a whole science in choosing the right regression model, which I’ll defer for now), you can use the LINEST function to return the coeffiecients dynamically. If the data source for LINEST is an Excel Table, then the coefficients will update automatically as new data are appended to the table. Using the coefficients supplied by LINEST allows construction of your regression prediction equation.

Another approach is to use FORECAST.LINEAR. This does not show you the equation but does allow calculation of linear predictions directly, based on a cloud of points. So, use with caution.

Worth noting that in either of these approaches one must be sure that linear regression is appropriate and this, of course, comes with the usual caveats of extrapolating outside the boundaries of one’s data.