XII. On the Comparison of various Tables of Annuities. 

 By J. W. LUBBOCK, Esq. B.A. F.R. & L.S. 



OF TRINITY COLLEGE, CAMBRIDGE. 



[Read March 30, 1829.] 



1. In last May I transmitted to the Philosophical Society 

 of Cambridge some remarks upon the construction of Tables of 

 Annuities ; my object in that paper was to shew how the 

 probabilities upon which Annuities depend, should be deduced 

 from Tables of mortality, and I gave in illustration some Tables 

 of Annuities calculated from observations of the mortality at 

 Chester, by Dr. Haygarth, which appear to have been made 

 with very great care. I have since compared these Tables with 

 a great many others, and I now jiresent the result of this 

 comparison. 



2. Very few registers of mortality give the deaths at every 

 year throughout life, they generally give the deaths between birth 

 and 5, 5 and 10,10 and 20, 20 and 30 and so on for every decade. 

 When the deaths are given between birth and 5, the living at 5, 

 at 20, 30, &c. are known, and in order to form a ccftnplete Table 

 of mortality it is necessary to interpolate the number of living 

 at each intermediate age. 



If the probability of an individual aged m years, living 

 n years be called p„„ „, if r is the rate of interest, and if the 

 same hypothesis of probability be adopted as in my former Paper 

 which amounts to increasing by 1 the deaths at every age, 

 Fol. III. Part I. Ss 



