Percent Integrated Gradient Field Ratio for hardat.ru6 at radius 0.0175 m. 
  where Integrated Gradient Field Ratio = Sum[(abs(Bn/B2*sin(-n*theta_south_pole ))] for harmonics 3-16  

    Imag        Integrated Gradient Field Ratio 
    (A)                         %                 
  ---------     ----------------------------------  
  46.89775                    1.66194
  70.95071                    1.66052
  94.98479                    1.67169
 119.93130                    1.68566
 149.99146                    1.70440
 175.07268                    1.72450