The expectation of life (cont.)
Exercise 2 (cont.)
A further exercise – South African mortality
If factors of 7, 7, 4, 4, 1 are entered into the factor boxes the resulting lifetable looks very roughly like the South African male lifetable of 1991, with an e0 of 58 years. This was indeed a good estimate of life expectancy in SA at this time, before the impact of AIDS really began to show. In the following 16 years life expectancy for males fell to a low of 53 years.
The reduction of life expectancy is very largely due to an increase in death rates, by a factor of about 2.5, in the ages 20-40 years. Simulate this in the (already simulated) SA lifetable by adjusting the 15-50 factor. What does expectancy (e0) fall to?
e0 is 54.6 years when factor 3 is 10 (2.5 × 4). Factors are now 7 7 10 4 1.
Life expectancy actually fell to 53 years in 2007. As well as the increase in death rates at ages 20-40 years there is also some increase in under 5 mortality (mostly between ages 1-4). What increase in young age mortality (first 2 factors) is necessary to bring down the e0 to 53 years?
Young age mortality also rose by about 40% so factors of 10 produce an e0 of 53. This happened because of social problems caused by deaths of parents and breadwinners and also mother-to-child transmission of HIV. Factors are now 10 10 10 4 1.
Life expectancy was expected to fall further but by 2007 anti-retroviral drugs became much more freely available and other programmes such as prevention of mother-to-child transmission and safe-sex messages started to become effective.
Since then LE has started to rise slowly and in 2012 was 56 years.