Progression most likely won't help u. It's accuracy of prediction which matters. Progression will finally let u down...You will finally see it. Hopefully u won't see it hard way.
http://www2.math.umd.edu/~ccremins/STAT100/Photos/Gaussian_distribution....
http://www2.math.umd.edu/~ccremins/STAT100/Photos/Gaussian_distribution....