You have deleted the first post, but I have had time to read and download it Mathcad file. More low I have attached to the message Mathcad file where as input data I used your data (X, Y), and as function of fit is used two models (this document demonstrates the use of Mathcad's "genfit" and "pwrfit" functions to fit data to a power curve model is used): 1. y=A*x^b 2. y=a*x^b+c
The document template is taken from center of resources "Mathcad Help". In the document I have only corrected input data (X,Y) and limits of boundaries for plots ([0;132], [0;95040]).