For part (ii) how is the Insurer’s net claims ratio (INCR) calculated for the Quota share plus XOL together arrangement? E.g. Year 1 I assumed would be 17435/26500 which is 66% approx not 68% unless it’s a rounding error.
Apparantly, you are calculating the Reinsurer's claims ratio. Insurer's net claims ratio(INCR) for this case is (GWP - RP)/(GCI-RR) i.e. (81308-17435)/(120456-26500) which is 67.98%(~ 68%)
