Magnetic field strength B at the magnetic pole for the axisymmetric l = 1 mode for the poloidal component, which is similar to l = 1 in Fig. 10. For the toroidal component, B represents the strength of the latitudinal or azimuthal field. The green horizontal dashed line represents B = 0. The fits are obtained with a magnetic cycle period of 14.4 yr which is twice the activity cycle period of 7.2 yr.