W. Perks in his recent paper (see p. 377 of this issue of the Journal) has shown how we may avoid tabulating net premiums or other special functions applicable to a particular valuation basis on individual valuation cards, and how a change may thus be made easily and rapidly from one valuation basis to another. The primary purpose of the present note is to develop Perks's principles and to test the methods on the actual valuation of the whole-life assurances of a life office.