PJ Media

Do you really think that an aging poulation is a sign of a high mortality rate, as Burnham would have us believe? Or, are you just being argumentative?

I would have thought it was self-evident. Apparently not.

It isn’t. And an aging population doesn’t seem to me to be a sign of a high mortality rate either. It seems to me a sign of a high mortality rate is a low life expectancy.

Nevertheless, I see the point about how a country with a high life expectancy could have a higher mortality rate than a country with a lower life expectancy.

It partly has to do with the probability of death being 1. And it partly has to do with the country mortality rate being a sort of a weighted average composed of the sums of total pop of a particular age and mortality rate of that particular age.

Suppose there are two countries, A – 75% of the population age 25 and 25% age 75; and B – 25% of the population age 25 and 75% age 75. Suppose the mortality rates for 25 year olds are A – 10%, B -5%, and for 75 year olds A – 80% and B – 50%. Total population of each is 1 million.

Obviously, the life expectancy and average age of B is much greater than A, and at either specific age the rate at which A’s die is much higher than the rate at which the B’s die.

Yet, in absolute numbers:

75,000 A 25′s, and 200,000 A 75′s die in any one year.

14,000 B 25′s, and 375,000 B 75′s die in any one year.

So the mortality rate of the country A is 275 per thousand, while the mortality rate of the country B is higher, 375 per thousand.

What the higher mortality rates at any specific age mean, is that the life expectancy of A is lower, and, that final, absolute probability of death = 1 is reached sooner in A.

It’s almost counterintuitive.