Computing the regression formula manually is tedious, even with only a few data points. As the number of data points increases, manual computation becomes impractical (When multiple regression is used, manual computation is virtually impossible.) Fortunately, spreadsheet such as Microsoft Excel7 have regression that will perform the computations. All that you need to do is input the data. The spreadsheet regression program supplies more than the estimates of the coefficients. It also provides information that can be used to see how reliable the cost equation is, a feature that is not available for the scatterplot and high-low methods.)