Magnitude corresponding to A_i, the i_M-band amplitude parameter of the model representing SN light curves, as a function of redshift, for fast-declining CC supernovae (top) and plateau ones (bottom), as measured in the 3-year SNLS data. Red dots come from fits to i_M-band light curves, green squares (resp. blue triangles) from fits in the r_M (resp. g_M) filter taken as estimates of A_i at higher redshifts (see text). Symbols with black borders indicate spectroscopically identified events. The curves are fits to the average redshift dependence of the magnitude, excluding points outside the dashed lines. As a comparison, black dots give magnitudes from spectroscopically identified SNe Ia.