Regression analysis helps you to use the relationship you create to predict for future development and growth. The FORECAST and TREND functions are used to perform linear regression analysis. These functions find the straight line relationship between one or more independent variables and a single dependent variable.

Independent variables are the variables needed to determine a prediction. The dependent variable is the variable for which you have current information or values but wish to predict its future state or values.
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Regression analysis can only be useful when you believe that changes in one set of variables is caused by the interaction between the dependent and independent variables.

This is the second part of this tutorial chapter. In this part, I will explicitly explain aand illustrate the business applications of the FORECAST and TREND function.

It is advisable that you first read the part 1:
PRACTICAL AND BUSINESS APPLICATIONS OF BUILT-IN FUNCTIONS IN MS-EXCEL
HOW TO USE THE FORECAST FUNCTION TO PREDICT FUTURE SALES IN EXCEL
Forecasting is the use of the known values, events or information about an event to predict its future occurrence or state. With MS-Excel, you can easily apply sophisticated statistical analysis techniques to your data. You can also use these techniques to stock prices, project expenses and other business trends.

The FORECAST function calculates, or predicts, a future value by using existing values. The predicted value is a y-value for a given x-value. The known values are existing x-values and y-values, and the new value is predicted by using linear regression. You can use this function to predict future sales, inventory requirements, or consumer trends.

The syntax is:
FORECAST(x, known_y's, known_x's)

The FORECAST function syntax has the following arguments (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.):

• X (required) is the data point for which you want to predict a value.
• Known_y's (required) is the dependent array or range of data.
• Known_x's (required) is the independent array or range of data.
NOTES:

• If x is nonnumeric, FORECAST returns the #VALUE! error value.
• If known_y's and known_x's are empty or contain a different number of data points, FORECAST returns the #N/A error value.

• If the variance of known_x's equals zero, then FORECAST returns the #DIV/0! error value.
PRACTICAL APPLICATIONS OF FORECAST FUNCTION IN SALES IN MS-EXCEL
Like I said earlier, the FORECAST function can be applied in various field. I will illustrate how the function is used to predict Sales and how to call up the function.
QUESTION:
The table shown in the spreadsheet is a Sales Record of Joe-links Services for the year 2016. Use the data in the figure below to predict the sales for the month of August.
Click http://www.microsofttut.com/2016/10/regression-analysis-using-forecast-and-trend-functions.html to read more.