Actuarial Aspects of Human Lifespans 13 



population disturbances. It is sometimes thought that the 

 hfe-table may be inaccurate at very advanced ages because of 

 errors in the stated age of the population and deaths involved. 

 In order to settle this issue a check was made of the ages of 

 alleged centenarians. The Home Office supplied a list of 

 persons (males and spinsters) reaching the age of 100 years to 

 whom a message of congratulation had been sent from 

 Buckingham Palace between April 1956 and June 1958 

 (married women were excluded because a maiden name would 

 be needed for checking the age and would not be known). 

 This group is somewhat selected but their age accuracy is 

 probably not seriously affected. For the 114 persons (53 males, 

 61 females) on the list, my colleagues at Somerset House 

 searched the birth registers for the relevant entries of a 100 

 years or so earlier (no small undertaking). Of these seven 

 could not be found and identification was doubtful in four 

 other cases. This left 103 identified and of these there were 

 92 cases where the birth entry agreed exactly with the 

 alleged date of birth while 11 showed errors as follows: 



1 day younger than stated 4 



1 day older ,, ,, 2 ^ 



2 days older ,, ,, 1 

 2 years older ,, ,, 2 

 5 years older ,, ,, 2 



11 



Serious errors amounted therefore to only 4 per cent of the 

 total. If anything these figures suggest a slight understate- 

 ment of lifespan. 



Discussion 



For the purpose of indicating the tendency for natural 

 lifespans to become longer, or for there to be a more general 



