Ratio of SNIa to CC events in positive T-type host galaxies as a function of SN multiplicity. The last point contains all SNe in galaxies which have been host to  ≥ 4 events, with a weighted mean of 4.7 SNe. Error bars on the ratios are calculated using Poisson statistics (if the number of SNe within a distribution is less than 100, then we use Gehrels 1986 to estimate errors). The x-axis errors bars on the last point for  ≥ 4 SNe show the standard deviation on the mean number of SNe within each galaxy within the bin.