The evolution of the birth rate of SNe Ia from a CD channel for a single starburst of 10¹¹ M_⊙ (top) and constant star formation rate of 5 M_⊙   yr^-1 (bottom) with different cutting times and different treatments of the CE, where Z = 0.02. The delay time in the figure does not include the spinning-down time from magneto-dipole radiation. Solid, dashed, and dot-dashed lines are the cases of α_CE = 2.0, α_CE = 3.0, and γ_CE = 1.5, respectively.