Sickness tables for non-standard periods are often encountered in Friendly Society practice—more often than may generally be expected. For example, in a substantial Order recently valued by the authors, the first fifty-six lodges were found to be using altogether forty-two such tables.

How to treat these benefits actuarially is quite a formidable problem, for no valuation factors are available for non-standard periods and none of the substitutes in general use is entirely satisfactory. For instance, the actuary can either use valuation factors for suitably chosen standard periods and make a rough over-all adjustment or he can turn to tables, such as those prepared by Rhodes,* and toil through the construction of the appropriate commutation columns. The first method is of doubtful accuracy and is very sensitive to variations in the age distribution, while the second involves an amount of labour which is generally quite unacceptable.