With varying sum insured values for Income Protection and large variations in the insurer's retention levels (see Table 1), quota-share reinsurance is optimal under the profitability criterion (see Table 2 and Fig. 2).
That is, quota-share enables retaining both the largest RPS ratio and the largest amount of premiums after paying claims (4.2 and A$47 mln. (US$40 mln.), respectively)