Gamma-ray background using the Rodney et al. (2014) (CANDELS) fit to the observational SN Ia rates with their prediction (solid black line) and the upper 1σ (blue dashed line) and 2σ bounds (red dotted line). With those rates, the SNe Ia cannot account for the observed gamma-ray background at the 2σ level (nor even at the 3σ level). The model used is the fully mixed W7 (W99b), but predictions for the other models are qualitatively similar.