The purpose of this paper is to expose in a structured way the Principal Components methodology, to show its applicability in reducing the dimensionality of the number of variables without losing the information contained in the original data set. An analysis was made in January 1991 of the macroeconomic vables, Monetaryari Policy, Price Policy, Economic Activity, Credit Aggregates and Trade Balance. With the models adjusted using the time series methodology, forecasts were made for the period from January to December 1992.