I am not a professional demographer. I dabble in fact and fiction. Mostly in fiction.
But as I have done so I have found that there is a good deal of problem with… definitions. The math of demography sometimes doesn’t match up with the culture of demography. And so, over time, I have gathered some definitions that they (professional demographers) use, and some that they don’t… but I think they should. Or maybe they do, but I haven’t seen them do it enough.
These definitions are not focused on the math… but on the reality of human behaviour. My desire is not to merely say ‘this is what is happening’, but to get at some of the why it is happening and, in the end, how we can change it.
So here is my list, as an amateur, of some demographic terms and their definitions.
Sex
INCEL
This term technically means involuntarily celibate and so would apply to both men and women, but at the time it tended to be used for men.
Let’s be careful here: this term is an internet meme, but it reflects reality. It is loaded with all sorts of political weight… but for demographers there is a physical reality. Ignoring the frustration of the young man who isn’t have sex… the demographer needs to note that he isn’t having children… because he isn’t having sex.
Living Together
This term, too, might seem simple: a man and a woman living in the same place and having routine sex. But because of sociological implications, they may or may not feel free to have children together.
Sleeping Together
This term is awkward as well, as it can cover such a wide range of behaviours. Are they coming together daily, weekly, or when he is in town?
Fertile Coital Rate
This term asks how often a woman is having sex in such a way that pregnancy is a viable possibility. This combines both how often she is having sex, and how often that sex is what moderns like to call ‘unprotected’. (A truly insane term.) It is not intended to take into account if she or her partner is involuntarily and unknowingly medically infertile. If they have rendered themselves sterile, or are infertile and know it, then this would NOT be a case of fertile coitus.
This term would also include vaguer things such as jobs that take one out of town, social disapproval of coitus in certain circumstances, pornography use… as they affect the fertile coital rate.
Society
TFR
Short for ‘Total Fertility Rate’, this is the standard term used when discussing demographic growth. It is the most fundamental fact about how a society is able to reproduce itself. It measures the number of children that women in a society have on average.
Cohort
A ‘cohort’ is, simply put, a group. In demographic research, it is typically used to describe an age group, or an age and location, or an age and culture group. So, for example, ‘All females between the ages of 20 and 25 in the Midwestern United States’. Because fertility behavior is very often dependent upon these factors: younger vs older women are more/less able to have children, women in a given society are more/less willing to have children, etc.
So the cohort “Unmarried American women aged 75 or older” is typically a very low fertility ‘cohort’, whereas the ‘women of childbearing age in Niger’ is typically a very high fertility ‘cohort’.
This principle is extremely important when projecting demographic growth or loss into the future. Women who don’t exist can’t have children. So it’s useless to speak of a society where every single woman has four children as having a high growth rate if there are very few women to have those children. Specifically speaking if the cohort of women who are of an age to reproduce is very small, that will produce a multiplicative effect. Very few women will have very few children, which will mean that they will be another cohort later on down the road that will produce very few children.
In the United States, this was seen in the opposite direction after the baby boom following World War II. The baby boom generation was very large, and so the generation of children that they had, when they reached reproductive age, also had a lot of children. Not because their TFR was necessarily large, but because there were a lot of them to have the children.
Group Fertility Expectation
Ok, not a great name for the term, but I think this is a hugely important idea. The question of, ‘When this girl grew up in her society, how many children did people around her think she would end up having?’. The societal expectation of how many was ‘too few’ and how many was ‘too many’.
And, obviously, the girl was a member of several groups. Her church group might have been set in the midst of a secular society. Her family might have two children in a society where three was the norm.
So this term is meant to capture the girl’s fertility expectation when she arrives at the age where she is expected to start having children. It would include, more tangentially, issues such as age of marriage, use of birth control, frequency of coitus, etc.
INCHEL
This term is sort of parallel to ‘INCEL’. However, it means ‘involuntarily childless,’ and it refers to women who had thought, when they were younger, that they would be having children but, through a series of decisions they made and biological reality, now realise they will never have any.
Like INCEL, we need to separate out the political wars on the internet and point out that, for demographers, the INCHEL is a real person, a real datum. Their society may have produced in them a desire to have children (their society or their biology), but their society also produced an inability. Whatever choices they made… didn’t work to produce children.
Marriage
This term is not as easy to define as it might seem. Leaving aside modern nonsense, going back into history, the legal status, rights, and duties of married people were different from age to age and place to place.
And ‘married’ people can also be living together or not… and not just because of ‘separation’, but also because of military duty, etc.
Parental Support Rate
A very vague term, representing how much support parents, or new parents, have in their parenting activities. Are their grandparents to help? Neighbours? Is wet nursing acceptable?
It would also include, on the negative side of the column, any societal disapproval, increased tax rate, inability to use a car (car seat laws, children not allowed in the front seat, etc.).
Math
MPAP
This word combines demographic facts with sociological implications. Other definitions of fertility use both the average, called the mean, and include childless women in their calculations. This term does not do so. And the reason for that is sociological.
This term is the ‘Median Parity amongst Parents’, and is the median number of children that a woman who does have children has. Thus, never ‘zero’.
For the purposes of demographic growth, it is completely unimportant how that growth is distributed. (i.e., if one woman has a hundred children, making up for twenty women that have none). However, for the purposes of a pronatalist society, and actual population growth, it is extremely important. A child who grows up in a household with only one child and his neighbours each only have one child will come to a subconscious understanding that one child is normal.
If, on the other hand, a child grew up with 4, 5, or even 8 siblings and most of the other children that they socialised with also had several siblings, then they would come to internalize the idea that having several siblings is normal. Even if there were large numbers of women around who had no children. What is important for this term is the environment that the child grows up in.
Replacement Fertility
This term, used by practically all demographic researchers, is deadly. It ostensibly means the number of children the average woman has to have in order for the society to ‘reproduce itself’. It is deadly because it is false in two different ways:
It doesn’t take into account a variety of factors. While it may be technically true, it presents an ‘average’ for something that applies to a population of women who are split into different groups. So the ‘average’ fertility of a female population where a large group is already infertile due to age is wildly misleading. Or one whose population pyramid is already so skewed that the population that can have children is small compared to the overall population.
It doesn’t take into account the fact that ‘replacement’ only replaces numbers, not society. Previous societies had much higher fertility rates, and thus actual population ‘pyramids’. A fertility rate which greatly flattens the pyramid will not result in the ‘replacement’ of the society… just the population. The society with a TFR of 4.0 is structured very differently, and will look very different, from one with a ‘replacement’ rate of 2.1.
So, in order to actually carry on a society, we cannot rely on anything so mathematically detached as ‘replacement fertility’. We have to look holistically at society and see how many children are needed at what ages to keep society going.
Completed Fertility
Measuring fertility is an impossible thing, due to the complexity of the various mathematical and sociological intersections. One term that isn’t used much, but is what people actually assume is being measured, is ‘completed fertility’. It can only be measured when a woman dies. (Technically, when she becomes incapable of bearing more children, but that is impossible to measure except vaguely, as this age varies for women.) It answers the question: how many children did a woman have?
This is what most of us naively assume TFR is measuring… but of course, as TFR is taken while women are still alive, it can’t actually do that for living populations. We might be able to measure the actual TFR of the US in 1810, but we can’t for 2010. We can only make projections.
Tempo Effect
In a bizarre sort of contradiction to ‘completed fertility’, we have ‘tempo effect’. A society whose women have three children each, immediately after getting married, which they do young, will have a much more positive effect on the population growth of a country than if those exact same women had married later and spread their children out.
This is because if you have children when you are young, they are able to reproduce themselves sooner. Which means the society will actually grow faster (or collapse more slowly).
False Fertility
There is a serious problem with modern demographic research: they fail to treat fertility as a closed system. IOW, people will speak of ‘immigration’ as a possible fix to population decline. But moving population from one spot to another won’t fix the problem, for two reasons:
The resulting population seems to typically come to share the TFR of the society they are joining.
It pushes the problem back one country. Westonia cannot solve their population deficit by continually importing people from Birthistan… unless Birthistan is producing enough children for both! IOW, the total TFR of the combined two countries would need to be at least replacement level.
So importing immigrants can be seen as a temporary fix, but as far as long-term trends are concerned, it fixes nothing.
Parity
The number of living children the woman has. The actual number that is important for demographic research needs to be something like ‘parity until successful reproduction’… i.e., there is a very real sense in which children don’t count until they, themselves, have started reproducing. So, perhaps, ‘PSR’?
Now, again, this cannot be measured ‘in real time’. But that doesn’t change the fact that it is what is actually being looked for… what actually affects societies. Demographics is a science of the present… but really of the future. It can only be estimated today… Any true measurement can only be of the past. We know that Abraham had many sons… who had many sons… who had many sons… but we cannot tell that about ourselves.
Nuptuality
The probability that a woman will get married. One might add in a subquestion of the age at first marriage. Perhaps ‘Primes Noces’? Because the research is quite clear: marriage people have a much higher rate of ‘fertility’… ie they tend to have more children. Some of which might be social; we all know of couples who were living together but are quite open about the fact that they aren’t going to have children until they get married.
Momentum
This term combines other terms into a moving system: how is the system moving in terms of population?
For my amateur audience, we need to see ‘momentum’ not just as some mathematical abstraction (smaller cohorts of children in the past produce smaller cohorts of fertile women, who produce smaller cohorts of children… etc) but to examine how each of the issues discussed here tends to echo through time. A child born in a small household will see that as normal… and be resistant to having lots of kids. A woman whose mother married late, divorced, talked trash about the men in her life…
A society that has a ‘dating’ system that produces very few marriages, and those late and fruitless, will come to the point where it can’t even imagine an alternative. A society that assumes that the couple will be on birth control for the first couple of years of their (already delayed) marriage.
All of those things have ‘momentum’. What happens today affects tomorrow.
Medicine
Medical Infertility Rate
There is an interesting fact of demographic language that ‘fertile’ and ‘infertile’ are not used as opposites. A ‘fertility rate’ means if women are having children, but ‘infertility’ means that they can’t… not that they aren’t, typically.
So it is important for any demographic discussion to recognise if their women (and their men, but this is usually less discussed) are ‘barren’… i.e., if they are incapable of having children. The math of fixing the problem will depend upon taking this into account.
Conclusion
This paper is not intended to merely present a series of dry, statistical terms, but to motivate a change of thinking. It is meant to be offensive… to the modern sensibilities that have created the demographic cliff we have driven off of.
You cannot fix a problem unless you acknowledge that it exists and your part in it. All over the world, ‘modern’ societies are dying. They are committing suicide. They are not only failing to reproduce themselves, but are mired in political and economic systems that require large numbers of children to grow up and enter the workforce to survive. And those children aren’t there. They won’t be there. Indeed, they can’t be there.
So any fix needs to take into account the coming disaster… and look beyond it.
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Von