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Hi R-Users, I apologize if it is too simple question for all. I have a multivariate dataset having 7 variables as independent and 1 dependent variable. 248 data points are there. I want to do out sample forecast first considering 156 points. So I'll have to start from 157th point and calculate the 157th y_hat value. In this way it will go to 248th data point. Can any one tell me how I can