About three years ago I made some calculations for my wife and I on
what our life expectancy could be expected to be (*1). I used several different
methods, looking more for trends than exact details. The bottom line was that
we each have an expectation of living into our mid-to-late-80s, with her life
expectancy a little longer than mine. In those calculations I went back to our
grandparents, but now I’d like to go back a few more generations.
With a relatively small number of ancestors at each generation, it only
takes one “outlier,” say an individual who passed away at age 35, to have a
significant effect on the average of individuals in that generation. However, I
believe that one needs to include them anyway. On the other hand, since we are
looking at individuals who lived long enough to marry and have children, we are
thus also excluding the impact of those who “died young,” so the below
statistics are not comparable to other studies which looked a life expectancy
in past generations. In order to increase the number of individuals being
considered, I’m going to take my ancestors and my wife’s ancestors together
instead of separately as I did in (*1).
Parents – average life span was 85
Grandparents –72
Great-grandparents –67
Great-great-grandparents –69
Great*3-grandparents – 69
Great*4-grandparents – 63
I’d also like to take a look at the range of ages in each generation.
The below is the number of individuals in each age-range.
20-29 – 0 0 0 2 0 0
30-39 – 0 0 3 2 3 7
40-49 – 0 0 1 2 1 6
50-59 – 0 1 3 2 6 9
60-69 – 0 2 1 3 10 8
70-79 – 0 3 6 8 10 16
80-89 – 4 2 2 9 8 7
90-99+ – 0 0 0 2 2 7
Total – 4 8 16 30 40 60
I’ve chosen to stop at this point, not because I don’t have any data,
but I’ve already begun finding situations where our family tree has holes in it
because I have not yet been able to fully populate all the branches (for
example, I only have both birth and death dates for 60 out of 128 possible
ancestors in the last column). This is especially true for those lines which
have more recent immigrants and where I don’t have easy access to foreign
records.
In looking at the distribution of ages, I have a couple of observations.
First, there are more “early deaths”, i.e. individuals who died prior to say 60,
in the older generations. And secondly, except for my parent’s generation, the distribution
curve for every generation tends to peak in about the same place, namely in the
70s. So, I decided to recalculate the average ages if one removed any of the “early
deaths”. The averages then, for each of these generations, were 85, 73, 75, 79,
75, and 77.
So, my conclusions, at least in looking at my and my wife’s ancestors
are the following:
First, the key difference over the last 200 years is not that people
are living longer, but that we have better medicine and other things that have
addressed diseases and conditions that caused early deaths in the past. If you
lived until the age of 60, then your life expectancy did not change that much.
Second, beginning with my parents’ generation, in addition to addressing
causes of early death, we have finally made some progress in increasing the life
expectancy of those who live to age 60. I don’t want to extrapolate this too
far just based on the above numbers since there are only four individuals
represented in the average for that generation, but the Social Security Administration
has calculated that individuals who reach the age of 65 have a life expectancy
in the mid-80s (*2). The data for my and my wife’s ancestors confirms this result.
Notes: