Evolution of the observable fraction of star formation, ﹩{f}_{{\rm{obs}}}(z)={\dot{\rho }}_{\star }^{{\rm{obs}}}(z)/{\dot{\rho }}_{\star }^{{\rm{tot}}}(z)﹩, where ﹩{\dot{\rho }}_{\star }^{{\rm{obs}}}(z)﹩ and ﹩{\dot{\rho }}_{\star }^{{\rm{tot}}}(z)﹩ represent the SFRDs in observable galaxies with M_UV ≤ −17 and all galaxies, respectively. Shown are the results integrated from the two LF models (Schechter as the orange line, and DPL as the purple line).