"Things You Wouldn't Know If We Didn't Blog Intermittently."
05 June 2014
Memento mori in graphic form
Found at Strategy and Analytics, where there is also a companion graph showing expected remaining years of life vs. current age. Data from the U.S. Social Security Administration.
I don't agree with this graph. Let's suppose the average female life expectancy is 80. Why is it that I would have a 50% chance of dying within a year as a 100-105 yr old female but only a 5% chance of me dying within a year when I'm 80?
I think the confusion comes from the concept of average life expectancy. This figure comes from death statistics over the whole population of a country including, for example, children. If you look at the source data for this graph, you can see that the probability of death of children under 1 is about the same as that of a 53 year-old for males and a 58 year-old for females. The probability then drops dramatically and keeps dropping until age 10, before starting to rise again.
This may be a bit of a grim realization, but this number of child deaths lowers the average life expectancy. If you survive until age 1, your expected age of death becomes a bit higher than that of a newborn. If you're 30 and still alive, you obviously can't die before 30 so all of the statistics of deaths of people under 30 don't apply to you. Effectively, the older you get, the older you can expect to live. You can see that on the second graph at the link: the life expectancy for females is 80 at birth, but it doesn't decrease by 1 year per year of life. An 80-year-old female can expect to live another 10 years, which is why she only has a 5% chance of dying within one year.
I don't agree with this graph. Let's suppose the average female life expectancy is 80. Why is it that I would have a 50% chance of dying within a year as a 100-105 yr old female but only a 5% chance of me dying within a year when I'm 80?
ReplyDeleteWhat don't you understand about older people being more likely to die than younger people?
DeleteI think the confusion comes from the concept of average life expectancy. This figure comes from death statistics over the whole population of a country including, for example, children. If you look at the source data for this graph, you can see that the probability of death of children under 1 is about the same as that of a 53 year-old for males and a 58 year-old for females. The probability then drops dramatically and keeps dropping until age 10, before starting to rise again.
DeleteThis may be a bit of a grim realization, but this number of child deaths lowers the average life expectancy. If you survive until age 1, your expected age of death becomes a bit higher than that of a newborn. If you're 30 and still alive, you obviously can't die before 30 so all of the statistics of deaths of people under 30 don't apply to you. Effectively, the older you get, the older you can expect to live. You can see that on the second graph at the link: the life expectancy for females is 80 at birth, but it doesn't decrease by 1 year per year of life. An 80-year-old female can expect to live another 10 years, which is why she only has a 5% chance of dying within one year.
I hope that helps.