How is the earned exposure calculated for instance Q2 - assume midpoint is mid may which gives 6.5 months unearned. Also why is the new rate unearned exposure out of 24 months?
Between mid-May and the end of the year there are 7.5 months, so the business in Q2 is 7.5 months earned by the end of the year - which gives earned premium of £137.5m and hence unearned premium of £82.5m. The business written in Q3 on the new rates will be 3.5 months or 7/24 of a year earned by the end of the year, using the 24ths method.
