Population Structures


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  • Outstanding presentation! Thank you for the specifics about the different populations. This is clearly the best presentation on Population Pyramids I have seen.
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Population Structures

  1. 1. 3. Population Structures
  2. 2. Population Pyramids The population structure of a country is usually displayed using a population pyramid graph (shown below). Population pyramids show the differences between the numbers of males and females as well as the number or percentage of people in each age category (know as the age-sex structure). Population pyramids can show: trends in birth and death rates, impacts of migration, impacts of wars or diseases and can give an indication of life expectancy. Data from population pyramids can also be used to calculate dependency ratios. Trend of declining birth rates since the 1970s Recent increase in birth rates Post-war baby boom High life expectancy with a significant % over the age of 80 Higher % of elderly females than males Large economically active age group 16 - 64 Straight sides of pyramid reflect low death rate High birth rates in 60s & 70s due to increasing wealth
  3. 3. Population Structures & the DTM The population structures change as countries develop and progress through the demographic transition model. The typical stapes of the pyramids are show below… Stage 1 Stage 2 Stage 3 Stage 4 Stage 5
  4. 4. Main elements of population structure Aspect Low High Number of males per 100 females Many women remain childless - reduced birth rate increases economic independence of women. Reduced numbers of males could be due to war or migration Substantial numbers of men unable to find a female partner – reduced birth rate. Possible increase in sex offences. Possible increase in urban unrest and ‘gang’ behaviour. At birth, ratio of M:F is 105:100. In the past this was evened out. In some countries, low status of women has led parents to selectively abort girls. Proportion of people under 15 Proportion of fertile individuals will be low in immediate future. Decline in birth rate. Higher proportion of the population will be ageing. 3rd or 4th stage of demographic transition - developed countries. Large numbers of fertile individuals in the immediate future. High birth rate, very young population. Children likely to be required to be economically active. 1st or 2nd stage of demographic transition - developing countries. Proportion of people over 65 Most dependants are children. Either life expectancy is low or population is in a period of rapid expansion. 1st or 2nd stage of demographic transition - developing countries Large numbers of old people are dependent - long life expectancy. High demands placed on welfare and medical services. 3rd or 4th stage of demographic transition - developed countries .
  5. 5. Kenya’s changing population pyramids Notice how the shape of the pyramid changes from having concave sides in 2001 to straighter sides in 2010 as a result of declining death rates. By 2020 there is a clear change in birth rates and a continued increase in life expectancy. The numbers of infants increases again between 2030 and 2040 as a result of the large number of people of child-bearing age. In 2050 the pyramid is clearly more representative of a country in stage 4 of the demographic transition model with low birth and death rates and a high life expectancy.
  6. 6. Dependency ratios Dependency ratios show the relationship between the number of economically active people in comparison to the number of dependent people within a population. It is calculated using the following equation: DEPENDENCY RATIO = (% UNDER 15) + (% OVER 65) X 100 % BETWEEN 15 & 64 In the UK in 2000… Dependency ratio = 53 (dependents on every 100 economically active people) In Kenya in 2000… Dependency ratio = 97 In Mali in 2000… Dependency ration = 112
  7. 7. Migration and population structure Migration can have a significant impact on the population structure of a country as shown by the 2 graphs… International migration often occurs among the younger sectors of the economically active population and can be dominated by young males. Many of the impacts on the countries involved are identified in the population change section. In the United Arab Emirates, Dubai is one of the world’s fastest growing cities. In 2007, half of the world’s cranes were working on building sites across the city. Migrants comprise 90% of the workers in the UAE and in Dubai, 2/3 of the population is made up of migrants. These 1 million migrants come from 160 different countries with the majority coming from S.E. Asia – India and Pakistan. Average pay among unskilled workers is $4/day, even with these relatively low amounts, workers often manage to save money to send back to their families in their source country – it is estimated that this could amount to $100bn every year. PROBLEMS Passports are often confiscated by employers to prevent the migrants leaving while they are under contract Cramped workers’ camps have been constructed in the desert There are many claims of discrimination and violence against employers Accident and suicide rates are high among migrant workers – 84 known suicides in 2006
  8. 8. Implications of an ageing population Stages 4 & 5 of the DTM Low birth rates and low death rates (although DR may gradually increase) CASE STUDY… The UK Stage 4 of the DTM Birth rate = 12 Death rate = 9 In 2010, the average life expectancy for people who turned 60 was 83 (another 23 years). The country therefore has serious problems of supporting millions of people who may be retired for 20 years. The problem is compounded by the fact that birth rates have been falling in the UK since the 1970s. 16.5% of the population is aged 0-14 and 16% were over the age of 65, with a median age of 40. IMPACTS There are benefits as well as problems of an ageing population: Benefits include – business opportunities for companies targeting the ‘grey pound’ such as SAGA insurance and Stannah Stairlifts. Retired people doing part-time work for companies such as B&Q (25% of their employees are over 65) are often very reliable and have greater skills and experience than younger workers. Grandparents often provide unpaid childcare allowing parents to go to work. Problems include – declining standard of living amongst elderly people who are dependent solely on a state pension – these people often rely on help from NGOs such as Age UK. Increasing numbers of people with heart disease, diabetes and cancers place an increased strain on the NHS. Housing needs change as elderly people often need single storey homes or sheltered accommodation. A growth in ‘grey power’ as elderly people are often more political active and will support political parties that will offers more to the over 65s. An increasing tax burden on the economically active – when pensions were first introduced in the 1900s, there were 22 working people for every pensioner, by 2024 there will be less than 3!
  9. 9. Implications of an ageing population CASE STUDY… The UK cont… SOLUTIONS In the 1970s the fertility rate in the UK fell below 2.1 which is the replacement level ( this has mainly happened as a result of the changing role of women in society and the increasing costs of raising children). This decline has compounded the problems of an ageing population. As a result, many politicians belief that immigration must be encouraged to bolster the numbers of economically active people and reduce the dependency ratio. This solution is often controversial with many groups of the general public. In 2004, the European Union was enlarged to include 10 Central and Eastern European countries which has resulted in an increase in immigration anyway. Polish migrants represent the largest single migration to the UK ever! From 2001 to 2008, net immigration added 180,000 people to the population of the UK every year compared with 90,000 people added from natural increase. From October 2011, the compulsory retirement age was completely abolished, allowing people to work for longer if they wish. In April 2010, the state pension age for women increased from 60 – 65 and from 2018, the state pension age for both men and women will rise to 66. Other solutions involve trying to encourage births through the provision of child benefits, tax credits and increasing the length of maternity leave.
  10. 10. Implications of an youthful population Stages 2 & 3 of the DTM High birth rates and declining death rates CASE STUDY… The Gambia Stage 2 of the DTM Birth rate = 45 Death rate = 15 Only 50% of people live in urban areas therefore there is a large rural population 40% under the age of 15 and only 3% are over 65 with a median age of 19. 90% of the population are Muslim (and many Islamic leaders have actively campaigned against the use of condoms) Dependency ratio is 90 compared to around 50 in the UK In 1990, a survey revealed that only 6% of Gambians were using contraception IMPACTS Schools overcrowded – at school in Banjul (the capital) pupils have to attend in 2 shifts 40% of people are literate Housing overcrowded – fertility rate is over 4 so the are many families with 6 or more children Money is limited for other improvements such as vital infrastructure – the roads still aren’t paved in Banjul and only 19% of roads are paved in the whole country GDP is growing at a rate of over 5% per year as there is a large, cheap workforce SOLUTIONS Government is trying to promote contraception in order to reduce birth rates, an NGO called futures provides subsidised contraception and tries to promote education of birth control especially via radio broadcasts in rural areas. Health care is being improved with a particular focus on improving antenatal care for pregnant women and paediatric care of young infants. Women are also educated about the benefits of spacing between each birth.
  11. 11. Implications of an youthful population CASE STUDY… The Gambia cont… SOLUTIONS Government is trying to promote contraception in order to reduce birth rates, an NGO called ‘the Futures Group’ runs a project called ‘Social Marketing’ where they provide subsidised contraception and try to promote education of birth control especially via radio broadcasts in rural areas. They have also established 350 new outlets for distributing condoms and to date have sold over 500,000 condoms and over 50,000 packets of contraceptive pills. Health care is being improved with a particular focus on improving antenatal care for pregnant women and paediatric care of young infants. Women are also educated about the benefits of spacing between each birth.