In 1965, Clarke and Preston submitted a paper to the Institute (JIA 92) which gave the results for the period 1947–63 of the mortality experienced by impaired lives who were issued policies by their office. In 1978, Clarke presented a paper (JIA 106) reporting on the experience of the next 10 years, viz. 1964–73. The primary purpose of this paper is to report on the experience of a further 10 years, viz. 1974–83.
By courtesy of the Government Actuary, the preliminary data relating to the proposed English Life Tables (no.14) were made available to the author. In this paper we describe briefly the graduation of the underlying crude mortality rates by cubic splines and give an outline of the salient features of the graduations finally adopted.