Add the year-end estimate of the losses that were outstanding one year earlier to the payments on those losses made during that year. The difference between that sum and the reserves that were established at the end of the prior year is the one-year reserve development. The ratio of one-year reserve development to prior year's surplus is the deficiency or redundancy. The acceptable range is less than twenty-five percent deficiency. Any redundancy is acceptable.
Add the year-end estimate of the losses that were outstanding two years earlier to the payments on those losses made during those two years. The difference between that sum and the reserves that were established at the end of the second prior year is the two-year reserve development. The ratio of two-year reserve development to the second prior year's surplus is the deficiency or redundancy. The acceptable range is less than twenty-five percent deficiency. Any redundancy is acceptable.
For the last two years the reserves as stated in those years are adjusted by the one-year or two-year reserve development as calculated in the above two ratios. This total is then divided by the net premium earned in the appropriate year to obtain the developed reserve to premium ratio. The estimated reserves required is the current net premium earned multiplied by the average ratio between developed reserves and earned premium for the last two years. The estimated deficiency is the difference between the estimated reserves required by the company and the actual reserves maintained. The estimated current reserve deficiency or redundancy is taken as a percentage of surplus and the acceptable range is less than twenty-five percent deficiency. Any redundancy is acceptable.
N.Y. Ins. Law § 4117