1. A method of fitting a curve to a plurality of data points comprising the steps of: a) fitting a first curve to a first set of data points selected from said plurality of data points; b) including other data points from said plurality of data points individually with said first set of data points in an iterative manner until an ending criteria is met to form another set of data points in response to another curve fit to said another set of data points upon each iteration that satisfies a first pre-determined condition; and c) accepting a final curve as a best fit curve for said plurality of data points.