Lesson video

Hello geographers.

My name is Mrs. Griffiths and today's lesson we are going to be looking at the links between levels of development and demography, which is the age makeup of a country.

So we're going to be thinking about how do different populations compare in terms of their level of development, but also the link therefore to the age makeup of that population.

Also, thinking about the other way round, how does the age makeup of a population affect the process of development? So thinking about links both ways, should we get started? And so our outcome for today is this.

I can understand the links between level of development and demography.

So that is what I'm hoping you're gonna be able to say by the end of the lesson.

We have some key words today also, so those are, demography, the study of population, its size, composition and change over time.

Birth rate, the number of births for every thousand people in a population per year.

Natural increase, which is when a population grows in size as a result of the birth rate being higher than the death rate.

Population pyramid, which is an age sex graph used to present the structure of a population that may resemble, sorry, a pyramid in shape and then a demographic transition model, which is a theoretical model that suggests how birth rate, death rate, and total population change over time.

How does demographic data vary between countries? That's the first question we're gonna be answering today.

And then we have a second question, what is the demographic transition model? But first let's have a think about this first one.

How does demographic data vary between countries? Development is the progress of a country in terms of wealth, use of technology and human welfare.

So that's our definition of development.

Oh, some old people.

So demography is the study of population, its size, composition, and change over time.

Countries at different levels of social and economic development have different demographic characteristics.

So more of the population, for example, might be old and retired.

There are a range of different data sets used to compare the demographic characteristics of countries.

Let's have a look at those different data sets.

So what could we look at? We have the crude birth rate for different countries, crude death rate, fertility rate, infant mortality rate, maternal mortality rate, and the dependency ratio.

So I'm going to be talking about these different data sets and thinking about what they can tell us about changing populations.

So the crude birth rate and death rate of a number of births or deaths for every thousand people in a population per year.

These rates can be used to compare countries because if you subtract, sorry, the death rate from the birth rate, we get something called natural increase.

Now natural increase is when a population grows in size as a result of the birth rate being higher than the death rate, it ignores migration.

So we're just thinking about birth rate and death rate.

Many LIC, so lower income countries have a youthful population and therefore a high birth rate and lower death rate.

Fertility rate is the average number of children born to a woman in her lifetime.

As countries develop socially as well as economically, the fertility rate and the birth rate will fall.

Women choose to start a family later and have fewer children.

Why might that be? Well, we have an answer here from Sophia who says, women who are able to complete their secondary education are more likely to go on to work outside the home before having children.

So that's absolutely right.

That has an impact on the fertility rate because women start a family later.

Infant mortality rate is the number of deaths of children under the age of one for every thousand live births.

While infant mortality rates in all countries have fallen since 1990 in lower income countries, so that's a good news story.

Many babies still die of preventable disease and that this is something that needs to be sorted.

Only a third of births may be attended by skilled healthcare workers.

So there's one reason perhaps why babies are dying of preventable disease, so that there's need for investment in healthcare.

As a result, there are big differences between the infant mortality rate of countries at different levels of social and economic development.

So for example, Pakistan's infant mortality rate was 25 times Sweden's rate in 2022.

Interestingly, Sweden was ranked 159 places higher than Pakistan in the UN's Human Development Index in 2022.

Maternal mortality rate is the number of women who die while pregnant or in childbirth per a hundred thousand births.

And here we have a map of maternal mortality rate across the world.

It's a choropleth map, so the darker the colour, the larger number of women who are dying per a hundred thousand births.

If we look at that map, what do you notice about the pattern of maternal deaths? Well Aisha has an answer for us here, she's noticed that the rate is higher in lower income countries.

So we know something already about the income of countries in, for example, central Africa, Western Africa, and Eastern Africa.

This is where some of the least developed countries are in terms of the economics.

And this is also some of the areas with the highest rates of maternal mortality.

Take a look at the scale at the bottom there for this choropleth map.

What do you notice about it? Well, we have an answer here.

Izzy says, while the colour appears to darken gradually by interval, the numbers jump up dramatically with most of Europe being in that category zero to 10 and the highest rates being over a thousand.

So it's interesting how unless you look at the scale on this, you don't realise how the maternal mortality rates are so very different around the world, pretty shocking stuff.

Around the world, the maternal mortality rate is the demographic rate that varies the most.

In fact, Nigeria's maternal mortality rate is a hundred times the UK's rate.

It's an indicator of the quality of healthcare, but also the social status of women and women's rights.

And we can see just how much it's varying there between say the UK and Nigeria, Afghanistan also having a very high rate.

Note this 2020 dataset is several years outta date.

So because it's old, it may well be inaccurate for us there.

So true or false? Fertility rate is the number of births for every thousand people in a population per year.

Pause the video and talk to your neighbour about this.

And if you said false, can you explain why? That's right, fertility rate is the average number of children born to a woman in her lifetime.

The number of births for every thousand people in a population per year is the crude birth rate.

Well done on that.

Another check for you then.

How many times higher is the maternal mortality rate in Nigeria compared to the same rate in the UK? Pause the video, you might need to do a calculation.

Well, the answer is more than a hundred times.

What's a possible limitation of this data set, however? Well, if you told me it's several years outta date, you are absolutely right.

So we do need to double check the dates of these data sets.

Quite right because it's 2020 data as we saw when I was introducing maternal mortality rate.

With COVID-19, we know that 2020 was an extraordinary year around the world.

So the question is can we draw wider conclusions from this year or not? Okay, so the overall structure of population also varies according to the level of development within a country.

Here we have a population pyramid for Nigeria in 2010, so it's a little while ago now, but might be about the time that you were born.

We can use an age sex pyramid known as a population pyramid to present data about population structure.

Here we have Nigerian 2010, but let's have a think about population pyramids.

What are they? What are the key features of a population pyramid? Well, essentially it's two bar graphs presented back to back.

Here on the left we have the male population and on the right we have the female population.

This population pyramid shows percentage of the population in five year age groups.

So if we look at our axis of the bottom, we can see it's going up in increments of 2%.

And if we look at that access, that access, sorry, that links the two bar graphs, it's showing us age groups and it's jumping up in five year age groups.

What does the shape of this population pyramid show? Well, from its wide base, we can see that the birth rate was high in Nigeria in 2010.

We can also see that it tapers rapidly towards the older age range reflecting a relatively low life expectancy at this time, remember we're looking at a population pyramid here for 2010.

Other sources of data confirm what the population pyramid is showing.

Life expectancy in Nigeria was only 54 years on average in 2010, by comparison, in the UK life expectancy was 81 years.

Nigeria's birth rate was 42.

1, in the UK it was 12.

9.

So that gives you an idea that actually some of the ideas we had just by looking at the shape of the pyramid were correct.

Quick check for you then.

A population pyramid shows you the structure of a population by what? And if you said A, age and sex, you are absolutely right.

By looking at the shape of a population pyramid, you can tell what? That's right, the answer is C, if the birth rate is high or low, well done.

What is the economic impact of different population structures? Well, it's a little bit easier to decide this if we change the colours of the population pyramid.

So in this age sex graph we've got, again, it's Nigeria 2010, but the colours of the bars are linked to one of three different economic groups.

So at the bottom of the graph, that wide base are the young dependents.

So these are people who are too young to work.

Then beyond that, we have in the age group 15 to 64, we have the working age group.

And then in yellow, the yellow bars represent the elderly dependents.

So these are the retired members of our population.

Here when we look at the shape, we can see the working age population must support many young dependents, many children in this population and a relatively small percentage of the population is made up of elderly dependents that retired.

We can use the percentage of people in each of these age groups to calculate something called the dependency ratio.

And here we have some statistics about Nigeria in 2010.

So the dependency ratio is calculated by taking the young dependence and adding them together with the elderly dependents and dividing that by the percentage of working age.

And then to get your ratio, you multiply the whole thing by a hundred.

So here if we look at Nigeria in 2010, this our calculation which we have rounded up to three significant figures.

So our dependency ratio is 89.

8.

So if we think about the economic impact of different population structures, as I say, Nigeria has a high dependency ratio of 89.

8 in 2010, meaning there was a large burden, sorry, on the working age population.

This is because the income of the working age population must be taxed to provide schools, hospitals, and pensions for those older and those younger members of the population who cannot support themselves.

By comparison, if we have a look at somewhere like Indonesia in 2010, Indonesia has a much lower dependency ratio of 51.

1 in 2010, meaning there was a smaller economic burden on the working age population at that time.

And if we think about, well what's the socioeconomic impact of different population structures? Like Nigeria, Indonesia is a newly emerging economy.

However, the difference in its population structure may go some way to explain why Indonesia was ranked almost 50 places higher than Nigeria in the UN's 2022 Human Development Index.

So if there was a smaller burden on the working age population to try to supply education for that huge population those young dependents.

So that was the real burden in Nigeria.

If there's less of that burden in Indonesia, perhaps, perhaps investment went into a whole range of different things have improved, sorry, quality of life in Indonesia by 2022.

Okay, true or false? A high dependency ratio shows that a large proportion of the population is young or old and depend on working age people to support them.

What do you think? Pause the video, discuss that with a partner.

And if you said true, can you explain why? That's right, a high dependency ratio indicates that a large proportion of the population are either too young or too old to work.

The higher the dependency ratio, the larger the economic burden on people of working age and arguably the sort of the lower quality public services that are provided as a result.

Practise task for you.

Question one asks you to complete the fact file about key demographic rates that we can see here.

So I can see some gaps within this table that we need to complete.

Question two asks you to calculate the dependency ratio in Indonesia and the UK in 2025.

So two calculations to do there and a handy hint here from Lucas.

So the first step is to add the young dependents to the old dependents.

Yeah, that's absolutely right.

And then question three asks you to explain how population structure has economic effects.

So pause the video now, have a go and then press play when you're ready to hear the correct answers.

Okay, so let's have a look at how we got on.

We've got this table to start with that you needed to complete.

Of course it was the fertility rate that is the average number of children born to a woman in her lifetime.

And the link to development is that higher, is a higher fertility rate in countries with a lower level of development due to, for example, lack of access to contraception.

Maternal mortality rate of course is the number of women who die while pregnant, or in childbirth per hundred thousand live births.

And the link to development was, it was higher.

This is a higher rate in countries with a lower level of development due to lack of access to healthcare before, during, and after birth.

And then infant mortality rate, I'm sure you have that right definition, which is the number of deaths of children under the age of one for every thousand live births.

The link to development is that again, this rate is higher in countries with a lower level of development due to a lack of access to healthcare such as vaccinations.

If you got all that right.

Well done.

Question two asked us to calculate the dependency ratio in Indonesia and in the UK.

And these are our calculations which we've provided to three significant figures.

So the UK having a higher dependency ratio there than Indonesia.

Did you get those right? And then question three, explain how a country's population structure has economic effects.

Your answer should include the following.

So let's have a look at our answer.

People of working age generate income for a country.

This means that if the percentage of people age 15 to 64, those are the working age people is low compared to the percentage of young people and elderly dependents, the proportion of the workers' income that must be spent on healthcare, education, and pensions to support those dependents is higher.

A population with a high dependency ratio is one in which the economic or tax burden on people are working age is high.

So this is the economic effects of population structure.

Okay, so we thought about demographic data and how it varies between countries, but what is the demographic transition model? Okay, so the demographic transition model maybe envisaged by this diagram.

So let's have a look at this diagram.

So we've got births and or deaths per thousand people per year on our Y axis.

And it appears to be showing change in the birth rate, death rate, and total population by stages.

Let's find out a little bit more about that.

So the demographic transition model is a theoretical stage based model that suggests how the birth rate, that's our green line and the death rate, that's our purple line and the total population, that's our black line change over time.

So if we think about our X axis, we have time on the X axis.

This model assumes that the country's level of social and economic development increases over time.

So we've got a general increase over time.

That's one of the assumptions of the model.

In stage one, the birth rate and the death rates of a country are high and fluctuate, meaning they go up and down as a result of disease, famine or war.

But over time with technological innovation there may be more food, better sanitation and healthcare.

Notice how the death rate appears to drop at the start of stage two before the birth rate falls in stage three.

So why do you think this time lag occurs between the fall and the death rate and the birth rate? What's going on? Well the fall in the birth rate is associated with later socioeconomic changes such as the education of women, access to contraception, and the reduced needs for children's labour.

And these are changes that would've occurred after the initial change where you've got a falling death rate perhaps associated with great availability of food.

The gap between the birth rate and the death rate is known as natural change.

Here we can see that natural increase is when the birth rate is higher than the death rate.

When natural increase is greatest, the total population as we can see on this model, is increasing fastest and it's increasing fastest in stages two and three of our model.

By stage four, both the birth rate and the death rate are low and the total population is much more stable.

But what do you think happens in stage five? So stage five is a recent innovation where geographers have taken this initial idea of the demographic transition model and they've sort of debated what actually stage five looks like.

So some people think with an ageing population, the birth rate will fall below the death rate, creating a period of natural decline.

In Japan and other HICs this is occurring now.

Other people suggest that the birth rate will ultimately increase.

The demographic transitional model is based on what happened in countries in Western Europe and North America.

And this is a key limitation of the model given the development of LICs and NEEs has been very different.

So we have to think about how widely it is applicable.

Secondly, migration is not shown in the demographic transition model and in some countries migration and its effects have been a major factor in population change.

So we've got two big limitations of this model, but equally it's quite interesting isn't it for us to think about is there a kind of a standard way in which countries have changed over time with the death rate falling first then the birth rate.

Pros and cons.

So the demographic transition model is a generalised theory about change over time.

But let's think about how does it compare to the experience of England and Wales that we have here represented on our graph.

So we don't have that third curve of total population, but we do have the birth rate and the death rate from the 1500s right up to 2015.

So here's our demographic transition model.

I wonder if you can look at it and think about what the similarities and differences are.

For example, where would you put the dividing line between stages one and two, two and three and three and four.

Pause the video and have a discussion with your partner about this.

Okay, so where have I added the line? So this is my line between one and two, 'cause we can see where the birth, the death rate, sorry, generally drops away.

Here we have our dividing line between two and three at the point at which we can see that birth rate really starting to fall alongside the death rate.

We've got that lag, haven't we? And then the dividing line between stages three and four, showing as that that birth rate and the death rate start to sort of fluctuate together at a low level, was that, was about, right? Is that what, just about what you thought.

It's interesting isn't it, where we've got a theoretical model and then we've got some real data and we're trying to make some comparisons.

So what really happened? Agriculture and industrial revolution drove population change in England and Wales from 1700 to 1900.

There was a growing gap between the death rate and the birth rate after 1750.

During this period, the population increased rapidly, but from the 1870s the birth rate began to fall.

Its interesting when we look at the changes in the birth rate and death rate.

In the 20th century, you can actually see where there are some peaks in the death rates associated with the first and second world war.

Although bear in mind that those crude death rates actually exclude military losses.

You can also see the baby booms that are subsequent to those two world wars.

So that's quite interesting, isn't it? The way the history's depicted in that data.

Okay, the stage of the demographic transition model are associated with different types of population structure.

So here we can see across these stages we've got a changing shape of population pyramid.

By stage three, the broad base of the pyramid has reduced.

And by stage four it's not really a population pyramid anymore.

It's not population pyramid shaped, is it? This means that the shape of a country's population pyramid may indicate what stage of the demographic transition model it has reached.

So let's think about our examples we looked at.

Which stage of the demographic transition model had Nigeria reached by 2010? Well, it's a tricky one.

Nigeria is actually in stage two in 2010.

The difference between stage one and stage two is the height of the pyramid.

So Nigeria had that height of pyramid, a significant percentage of people are living to age 65 plus.

However it shape doesn't match stage two exactly as Nigeria still had a very high infant mortality rate in 2010.

And so still a very high birth rate.

One for you then, what stage of the demographic transition model had Indonesia reached by 2010? Well, Indonesia had reached stage three of a demographic transition model by 2010.

And we can see that those corners have been chopped off the pyramid as the birth rate is no longer so high and the population is starting to change shape.

Well done if you've got that one.

What might be the economic effects of this change in population structure? So we're back to looking at Indonesia, but I'd like to compare for you Indonesia in 2010 and Indonesia in 2040.

Well, if we think about those elderly dependents, pension and healthcare costs increased with a larger proportion of retirees.

So by 2040 they're gonna be more old people that are retired and living in Indonesia.

The larger percentage of people of working age means there'll be more earners and lower education and childcare costs by 2040.

So we can see that that this demographic change over time will have an important effects for the economy.

True of false? The proportion of young dependents will be less in Indonesia by 2040, so this age group will be less of an economic burden.

Pause the video and talk to your partner.

And if you said true, can you explain why? The answer we have here is workers must earn to pay for education and healthcare for those unable to work.

So fewer children benefits the economy in the short term.

So it's a benefit for all those workers.

Okay, some practise task for you.

Here's the first one.

Complete the table below the model stating whether in each population indicator is high, low, stable, increasing or decreasing.

And if so, how rapidly.

So you've got that table to complete, looking at those three curves in our model.

Second task, describe two differences between these projected population structures.

Hint, you need to use data.

So we're comparing the UK in 2040, so the projected population structure and Indonesia in 2040.

And then third task for you, what stage of the demographic transition model you with the UK's population structure in 2040? And I want you to explain your answer.

Okay, so we need to grab a pen.

I'd like you to pause the video, have a go at those activities.

I know you can do it and then restart it when you want to check your answers.

Okay, first up, how did you get on completing that table? Yeah, so the birth rate in stage one is high, the death rate is high and the population's stable.

Stage two was sorted for you, but for stage three, did we get birth rate was rapidly falling? Death rate is low and stable and the population is still increasing.

By stage four we have low, low increasing, and then in stage five, did you get the idea that the death rate's probably quite low? Then we have our second task, which is to describe two differences between these projected population structures.

So let me read what we had.

The proportion of the population who are at the retirement age in the UK is higher than in Indonesia in 2040.

Only the 65 to 69 age group in Indonesia includes 2% of the population or more for both males and females.

By contrast, the young dependent population in Indonesia appears to make up a larger proportion, e.

g.

almost 7% males and females in every one of those three young dependent age groups compared to the UK where young dependents make up about 5% only per five year age group, males plus females.

So, what the person's done with this answer is they've taken the elderly dependents and they've taken the young dependents and they've made some direct comparisons using data.

So detailed answer there, well done if your answer looks a bit like that.

Last one was a bit of a tough one, wasn't it? What stage of the demographic transition model would you associate the UK's population structure to be in 2040? And you needed to explain your answer.

So I'm guessing you probably said it's likely to be in stage five of the DTM with very low birth rate and a fairly low death rate and potentially a period of natural decline.

The base of this pyramid appears to be tapering.

So here's my explanation, indicating a falling birth rate.

Also the percentage of people living in to 65 to 70 and 70, 75 years is greater than the nought 15 age groups, both male and female and equal to some of the working age groups.

So I've given some data there to explain what my kind of idea is about how this population is changing.

So well done again if your answer is detailed like this one.

In summary, how do we get on? Well, we've covered a lot again, but what have we covered? Countries at different levels of development have differences in their demographic characteristics.

Demographic characteristics include birth rate or fertility rate, death rate, maternal mortality rates, and population structure.

Population pyramids enable us to compare the population structure of countries and understand the economic impact of different structures by calculating the dependency ratio.

And there are links between the stages of the demographic transition model and the level of social and economic development around the world.

So well done.

I think you've really engaged with those practise tasks today and we had a lot to do, didn't we? I look forward to seeing you again soon.