1. The Human Population

2. Human populations grow or decline based on three factors: 1. births 2. deaths 3. migration

3. Instead of using the total numbers of births and deaths per year, demographers use birth rate and death rate. Birth rate, or crude birth rate is the number of live births per 1,000 people in a population in a given year. Death rate, or crude death rate is the number of deaths per 1,000 people in a population in a given year.

4. The rate at which the world’s population increases has slowed, but the population is still growing exponentially at a rate of 1.22 %. Every time your heat beats, 2.4 more babies are added to the world’s population. That is about 225,000 more people each day – 97% of them in developing countries.

5. Exponential population growth has not disappeared but is occurring at a slower rate. The rate of the world’s annual population growth (natural increase) dropped by almost half between 1963 and 2008 from 2.2% to 1.22%. But during the same period the population base doubled……remember exponential growth.

6. An exponential growth rate of 1.22 % may seem small, but in 2008 it added about 80 million people to the world’s population, compared to 69 million in 1963. An increase of 82 million people per year is roughly equal to adding another New York City every month, a Germany every year, and a United States every 3.7 years.

7. In 2008, the population of developed countries was growing at a rate of 0.1% while developing countries were growing 15 times faster at 1.5 %. As a result of these trends, the population of the developed countries, currently at 1.2 billion, is expected to change little in the next 50 years. In contrast, the population of the developing countries is projected to rise steadily form 5.2 billion in 2008 to 8 billion in 2050. The six nations expected to experience most of this growth are (in order) India, China, Pakistan, Nigeria, Bangladesh, and Indonesia.

8. The five countries with the largest number of people: 2. India (1.25 billion people) 1. China (1.36 billion people)

9. 3. United States (322 million people )

10. 4. Indonesia (249 million people) 5. Brazil (200 million people)

11. Fertility is the number of births that occur to an individual woman in a population. Two types of fertility rates affects a country’s growth rate. 1. Replacement-level fertility the number of children a couple must bear to replace themselves (2.1 in developed countries and as high as 2.5 in some developing countries – mostly because some female children die before reaching their reproductive years) 2. Total fertility rate (TFR) the average number of children a woman typically has during her reproductive years

12. Total Fertility Rate (TFR) in 2008 Average global TFR – 2.6 children per woman Developed countries – 1.6 children per woman Developing countries – 2.8 children per woman Highest TFR is in Africa – 5.2 children per woman

13. The population of the United States has grown from 76 million in 1900 to 304 million in 2008, despite oscillations in the country’s TFR and birth rate. A sharp rise in the birth rate occurred after World War II. The period of high birth rates between 1946 and 1964 is known as the baby-boom period. This added 79 million people to the U.S. population.

14. About 2.9 million people were added to the U.S. population in 2008 (one person every 11 seconds). Approximately 66% of this growth was the result of more births than deaths and 34% came from legal and illegal immigration (with someone migrating to the U.S. every 32 seconds). The medium projection for the U.S. population is an increase from 304 million in 2008 to 438 million by 2050 and reach 571 million by 2100.

15. Many factors affect a country’s average birth rate and TFR 1. The importance of children as a part of the labor force proportions of children working tend to be higher in developing countries, especially in rural areas where children begin working to help raise crops at an early age 2. Cost of raising and educating children birth and fertility rates tend to be lower in developed countries, where raising children is much more costly because they do not enter the labor force until they are in their late teens or 20s 3. Availability of private and public pension systems pensions eliminate parents’ need to have many children to help support them in old age

16. 5. Educational and employment opportunities available for women TFRs tend to be low when women have access to education and paid employment outside the home 6. Infant mortality rate In areas with low infant mortality rates, people tend to have a smaller number children because fewer die at an early age. 7. Average age at marriage (or average age at which women have their first child) Women normally have fewer children when their average age at marriage is 25 or older. 4. Urbanization people living in urban areas usually have better access to family planning services and tend to have fewer children

17. 9. Availability of reliable birth control methods allows women to control the number and spacing of children 10. Religious beliefs, traditions, and cultural norms some countries and / or religions favor large families and strongly oppose abortion and birth control 8. Availability of legal abortions The United Nations estimates that there are about 46 million legal and illegal abortions each year.

18. Click picture for the current world and U.S. population.

19. The rapid growth of the world’s population over the past 100 years was not caused by a rise in the crude birth rate. Instead, it was caused largely by a decline in crude death rates, especially in developing countries. More people started living longer and fewer infants died because of increased food supplies and distribution, better nutrition, medical advances such as vaccines and antibiotics, improved sanitation, and safer water supplies (which curtained the spread of many infection diseases).

20. Two useful indicators of overall health of people in a country or region is: 1. Life expectancy the average number of years a newborn infant can expect to live 2. Infant mortality rate the number of babies out of every 1,000 born who die before their first birthday

21. Between 1955 and 2008, the global life expectancy increased from 48 years to 68 years (77 years in developed countries and 67 in developing countries) and is projected to reach 74 by 2050. Between 1955 and 2008, life expectancy in the United States increased from 47 to 78 years and, by 2050, is projected to reach 82 years. In the world’s poorest countries, however, life expectancy is 49 years or less and may fall further in some countries because of more deaths from AIDS.

22. Infant mortality is viewed as the best single measure of a society’s quality of life because it reflects a country’s general level of nutrition and health care. Between 1965 and 2008, the world’s infant mortality rate dropped from 20 to 6.3 in developed countries and from 118 to 59 in developing countries. More than 4 million infants (most in developing countries) die of preventable causes during their first year of life – an average of 11,000 mostly unnecessary infant deaths per day. The U.S. infant mortality rate declined from 165 in 1900 to 6.6 in 2008.

23. Population Age Structure The number of people in young, middle, and older age groups determines how fast populations grow or decline. As mentioned earlier, even if the replacement-level fertility rate of 2.1 were magically achieved globally tomorrow, the world’s population would keep growing for at least another 50 years (assuming no large increase in death rates). The reason is a population’s age structure (the distribution of males and females in each age group.)

24. Demographers construct a population age structure diagram by plotting the percentages or numbers of males and females in the total population in each of three age categories: prereproductive (ages 0-14), reproductive (15-44), and postproductive (45 and up).

25. Age structure in developing countries vs. developed countries

26. The number of people under age 15 is the major factor determining a country’s future population growth. Any country with many people below age 15 has a powerful built-in momentum to increase its population size unless death rates rise sharply. Nearly 28% of the people on the planet were under 15 years old in 2008.

27. Between 1946 and 1964, the United States had a baby boom that added 79 million people to its population. Over time this group looks like a bulge moving up through the country’s age structure. 2005

28. Baby boomers now make up nearly half of all adult Americans. As a result, they dominate the population’s demand for goods and services. In 2011, the first baby boomers turned 65, and the number of Americans over age 65 will grow sharply through 2029. According to some analysts, the retirement of baby boomers is likely to create a shortage of workers in the U.S. Much of the economic burden of helping support a large number of retired baby boomers will fall on the baby-bust generation (people born between 1965 and 1976).

29. By 2050, the United Nations projects that the population size for most developed countries (except the United States) will have stabilized. If population decline is gradual, its harmful effects usually can be managed. But rapid population decline, like rapid population, can lead to serious economic and social problems.

30. Family planning has been a major factor in reducing the number of births and abortions throughout most of the world. Family planning provides educational and clinical services that help couples choose how many children to have and when to have them. Family planning has been a major factor in reducing the number of births mainly because of increased knowledge and availability of contraceptives. According to the U.N., 58% of married women ages 15-45 in developed countries and 54% in developing countries used modern contraception in 2008.

31. Studies indicate that family planning is responsible for at least 55% of the drop in total fertility rates (TFRs) in developing countries, from 6.0 in 1960 to 3.0 in 2008. Two problems remain: 1. 42% of all pregnancies in developing countries are unplanned and 26% end with abortion 2. An estimated 201 million couples in developing countries want to limit the number and determine the spacing of their children but they lack access to family planning services.

32. Women tend to have fewer children if they are educated, have a paying job outside the home, and do not have their human rights suppressed. Globally, women account for two-thirds of all hours worked but receive only 10% of the world’s income, and they own less than 2% of the world’s land.

33. Women make up 70% of the world’s poor and 60% of the 875 million illiterate adults worldwide who can neither read nor write.

34. Cutting Global Population Growth Experience indicates that the best way to slow population growth is a combination of investing in family planning, reducing poverty, and elevating the status of women. The Conference on Population and Development set a goal to encourage action to stabilize the world’s population at 7.8 billion by 2050 instead of the projected 8.9 billion.

35. Ways to meet the Conference on Population and Developments plan include: 1. Providing access to family planning 2. Improve health care for infants, children, and pregnant women 3. Develop and implement national population policies 4. Improve the status of women and expand education and job opportunities to young women 5. Provide more education, especially for girls and women 6. Increase the involvement of men in child-rearing responsibilities and family planning 7. Sharply reduce poverty 8. Greatly reduce unsustainable patterns of production and consumption

36. Click for the 21 min. Story of Stuff.