If I don't get this blog written, I may never blog again. *grin* I slipped into this topic accidentally, several posts ago, pretty well against my will. It's too much like teaching. Teaching is a fine thing to do, but you have to complete topics even when you'd just as soon move on. I'd rather keep my blog more personal and let my random thoughts and observations take me where they will rather than lecture on topics.
You will see, if you have been paying attention, that there is a new and final section added to the graph above: phase 5 of the demographic transition model. You will see a question mark in the phase because we don't truly know what will happen as it unfolds. (Please note that I had trouble with my drawing in adding this stage. It would have been better to have drawn the whole graph at the beginning rather than add to it. Technical skills, or the lack thereof, notwithstanding, however, the information is more or less correct.)
What you see in stage five is the crossing of the birth rate and death rate lines. If a country's fertility rate declines to below replacement levels, which is 2.1 per children per woman, over the long haul, the resultant aging population structure will, eventually, mean that the death rate will exceed the birth rate.
This is not conjecture, but reality. The world's more developed countries now average a fertility rate of only 1.6 children per female. Obviously, this means that the typical couple does not replace itself — the couple (two people) only reproduce one-and-a-half children (approximately). However, for the time being, that is still enough for most developed countries to grow their total population.
How can that be so?
It's simple really. Past population growth, such as the post-war baby boom, left us with a lot of couples to make babies. Even if they didn't make many babies per couple, they still made lots of babies as a group. In fact, there have been many more baby-makers in our society than old people. In other words, despite the decline in the fertility rate (the number of children that a woman bears), the birth rate has continued to exceed the death rate in most developed countries.
Nevertheless, the gap between birth rates and death rates has narrowed, and eventually they will cross each other — or so it seems. Developed countries will enter the phase of negative population growth. This can be mitigated to some degree by immigration. Not only does immigration add to the population in the moment, but it also increases the future birth rate to some degree because it is usually younger couples who are accepted into new countries. These couples also tend to come from areas of the world where higher birth rates are the norm. Where a native-born couple would tend to have one or two children, an immigrant couple might be more likely to produce three or four offspring.
Immigration notwithstanding, it will be hard to admit and absorb enough immigrants to avoid reaching negative population growth at some point.
Remember, however, that this is only occurring in developed countries. There is still a very real population explosion occurring in less developed countries. Although their fertility rates are decreasing significantly, the average third-world woman still gives birth to 2.84 babies. That is projected to fall to about 2.17 by 2050 — essentially replacement level. So, there is still a lot of population growth to occur in LDCs, probably three to four billion people, before the whole world reaches a no-growth stage (or stage five). Therefore, although population is set to soon decline in DCs, it will hardly put a dent world population growth.
Jordan, for example, will still double its population from about 6 million in 2005 to about 12 million in 2050. Morocco will expand from 32 million to 50 million, Rwanda from 8 million to 20 million. All of these countries are or soon will be lowering their birth rates dramatically, but there remain many young couples to reproduce children. (Note: these three examples were chosen at random and not for effect.)
Meanwhile, some European countries are already in stage five and already experiencing negative population growth. Germany's growth rate currently stands at -0.2%; its population growth has stopped, and its population will fall from its current 82 million to about 73 million by 2050. Poland will decline to 32 million from 38 million. France lags a little further behind in the process; it will grow very slowly from its current 60 million to about 63 million in 2030 before it then declines to 61 million in 2050.
The non-European developed nations are not as demographically advanced as their European counterparts. The North American countries will continue to grow until mid-century or beyond. The USA will still be growing by 0.7% in 2050 when it will house 420 million people, up 125 million from today's 295 million (note: the USA's present growth rate is 1.7%), for its fertility rate remains high (for developed countries) at 2.1/woman. Canada's fertility rate is lower — 1.6 — and it's growth rate will be as low as 0.2% by 2050. Likewise, Australia's fertility rate is 1.8, and it will grow moderately until 2050 when its growth rate is expected to be 0.1%.
However, even these slower, and not yet negative, growth rates have repercussions. Our society is aging. We don't build schools; we build nursing homes. An older population requires more social services, yet it has a smaller work force to sustain it. The USA, for example, finds itself looking at ways to make Social Security sustainable. In Canada, we have already raised the old-age-pension tax moderately. Another thing: traditionally, older people have less disposable income to spend than working people, and even if they do have money to spend, they tend to hoard it more. That could hurt the economy, but that scenario may not come to pass as baby boomers won't necessarily stay home and dine on toast as their predecessors might have been wont to do. Still another concern is that people will have to work longer. The raising of the pension-able age beyond 65 is already being discussed and may become necessary because developed countries could soon begin to endure a shortage of workers. Canada has already passed a law making it illegal to make retirement at 65 mandatory. Although that may only yet apply to government works (I'm not sure), you can see where we may be headed.
Low or negative population growth isn't and won't necessarily be an economic disaster, but it may require changes in the way we think about our working lives. Also, low and negative population growth in the relatively lowly-populated developed countries does little to slow total world population growth and does nothing to halt still rapidly glowing populations within the less developed parts of the world.
To summarize these posts:
- we in the western world (developed countries) had a population explosion as a result of the industrial revolution;
- the third world (less developed countries) are experiencing a large population explosion resulting from the aid of western nations;
- fertility rates are decreasing in the LDCs, and most population growth will end late this century or early next, probably with about 4 more billion people being added to the planet;
- and, fertility rates in DCs, below replacement level, are already resulting in negative growth in some European countries and slow growth in most developed nations.