Incurred but not reported. It's a # insurance companies use to project losses.
To explain loss ratio we have to start by the factors included in a loss. The loss factors are: Claims paid plus net reserves plus incurred but not reported (IBNR) plus provision for adverse deviation (PAD) Total them and substract your total with Total recoveries (actual +potential) You now have the total loss. Once we have these factors, we can divide the loss by the earned premium to obtain the ratio.
Calendar Year Experience: Simplistically, the matching of all losses incurred (not necessarily occurring) within a given twelve-month period, usually beginning on January 1, with all premium earned within the same period of time. Incurred losses will include the change in IBNR More specifically, the total value of all losses incurred (not necessarily occurring) during the calendar year is divided by the Accounting Earned premium for this same exposure period. Losses incurred are equal to the sum of losses paid, plus the outstanding loss reserves at the end of the year, less the outstanding loss reserves at the beginning of the year. Once calculated for a given period, calendar-year experience never changes.