Towards a precision measurement of the muonpair asymmetry in $\it{e^+e^-}$ annihilation at $\sqrt{s}=10.58$GeV

The Belle detector was operated at the asymmetric electron-positron collider KEKB in Tsukuba, Japan, between 1999 and 2010. Being designed as a so-called B-Factory, its center-of-mass energy was in the range of the Y resonances, with the bulk of the data taken at Y(4S) (10.58 GeV). The large available data sample (more than one billion muon and tau pairs) at Belle allows precision tests of electroweak predictions at energies below the Z-pole. The Standard Model predicts interference effects between gamma and Z-boson exchange in fermion pair production which cause a forward-backward charge asymmetry AFB. This asymmetry is related to the weak mixing angle sin2(θW) and is energy dependent in the SM. Any deviations from the predicted energy dependency hint to New Physics. Within this talk, the current status of the analysis of the muon pair charge asymmetry will be presented