Example. Population. Age and Sex Structure. Age Structure. Unit 5: Population Structure & Characteristics. How large the population is (size)?

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1 Population How large the population is (size)? What kind of population a country has (structure)? Example The debt crisis Population: Greece 11 M, Spain 47 M, Italy 61 M Why are these countries experiencing the debt crisis? Some scholars argue that structure is more important than size Unit 5: Population Structure & Characteristics Age and Sex Structure Household Structure Urbanization Age and Sex Structure Age/sex structure Age Transition Population aging Age Structure Median age U.S.: 32.9 (1990), 35.3 (2000), 37.2 (2010) Greece: 42.5 (2011); China:

2 Age Structure Dependency ratio: U.S.: P 0-14 :20%; P 15-64: 67%; P 65+: 13% What is the dependency ratio in the US? A) 0.49 B) 0.30 C) 0.19 Measure socio-economic impact of age structure For comparison China: P 0-14 :18%; P 15-64: 74%; P 65+: 9% YDR=0.24, ODR=0.12, DR=0.36 United States If you can choose, where would you live? Demographic Dividend A rise in the rate of economic growth due to a rising share of working age people in a population, which is often a result of falling fertility rate and the youth dependency rate. East Asian Miracle Ratio of Workers to Dependents, by Region Where will the next miracle be? A) Arica B) East Asia C) S. Central Asia D) Latin America Africa East Asia South Central Asia Latin America and the Caribbean Note: People 15 to 64 are considered to be workers; people 14 and younger and those over 65 are considered to be dependents. Source: United Nations, World Population Prospects: The 2002 Revision (medium scenario), Population Reference Bureau 2

3 Age/Sex Structure Median age Dependency ratio Sex ratio SR=(Male/Female)*100 Normal sex ration at birth: Age/Sex Structure Median age Dependency ratio Sex ratio Why do we care about sex ratio? Population pyramid A graphic representation of the distribution of a population by age and sex 3

4 Population Structures by Age and Sex, 2005 Millions Source United Nations, World Population Prospects, The 1998 Revision Less Developed Regions Age More Developed Regions Male Female Male Female Demographic Transition Please identify what kind of communities these pyramids are for Early Intermediate Late Young Intermediate Old Impact of Population Processes Mortality Gender difference in mortality --> feminization of the elderly population Mortality declines : In high mortality population: younger population due to lower IMR In low mortality population: aging population Mortality increases : the young and the elderly suffer Fertility Long-term effect (e.g. baby boom in the U.S.) 4

5 What can you tell from this pyramid? Which population is this pyramid for? Age Transition: Impact of Population Processes Mortality Fertility Migration/immigration 5

6 Age Transition: Impact of Population Processes Mortality Fertility Migration/immigration What kind of immigration policy should the U.S. have from the perspective of age/sex structure? Around Palestine/Israel Million Mostly Young People Lebanon 3.7 MM Syria 17.2 MM Jordan 5.3 MM Gaza Strip 1.2 MM Israel 6.0 MM West Bank 2.2 MM Egypt 70.7 MM Saudi Arabia 23.5 MM Iraq 24.0 MM Sudan 37.1 MM Somalia 8.5 MM Yemen 18.7 MM Team Activity Create a Pyramid List potential consequences of such populations in the region? Population pyramid for any country and its change over time 6

7 Age Transition: Dynamics of Age/Sex Structure Age Transition a shift from a young population with more males to an older population with more females Stable population: stable age/sex structure (same %, size could grow) Stationary population: A special type of stable population stable size & age/sex structure Zero Population Growth (ZPG): Only stable size ZPG now or later? ZPG Now ZPG Later Age Transition: Dynamics of Age/Sex Structure Population Momentum Potential for increase in population size due to a young age structure, even with replacement level fertility Population Aging Individual aging Biological aspects Senescence; 65 Social aspects Social status and roles Does the old have higher status than the young? The elderly lose status during the modernization process, but gain status again afterwards Population Aging Trends in Aging, by World Region Population Ages 65 and Older Percent Individual aging Population aging In 2010, 529 Million, 7.4% of world pop MDCs: 16% Uneven distribution (41% in developed nations) Growing faster than world pop (2.44% vs. 1.43%) World Population Aging Clock World Africa Asia Latin America/ Caribbean More Dev eloped Regions Source: United Nations, World Population Prospects: The 2002 Revision (medium scenario), Population Reference Bureau 7

8 Population Aging Individual aging Population aging Number, proportion, growth Impact of population processes Declining mortality Declining fertility Migration (in-mig and out-mig have different impact) Population Aging Individual aging Population aging Sex/age structure Feminization of old age Women and Aging World Population, by Sex, at Specified Age Groups, 2025 Percent All Ages Ages 60+ Ages 80+ Women Men Source: United Nations, World Population Prospects:The 2002 Revision (medium scenario), Population Reference Bureau 8

9 Population Aging Individual aging Population aging Sex/age structure Feminization of old age The third age (the young-old): The fourth age (the old-old): 75+, or 85+ Why? Population Aging Social cost of an aging population Who should pay for the elderly? Who will pay for baby boomers to retire (U.S.)? Babyboomers start to retire in about 2010 In 1960s: 4 workers for every retiree, by 2030, two workers. Chile model: people must save for their own retirement; forced by the government Postpone retirement? 70, 75, 80? Tax increase or tax cut? Social security reform? Replacement immigration? Population Aging Impact of an aging population E.g. Retirement of Baby Boomers Impact on social security? Impact on housing market? Impact on health care? Impact on U.S. economy? Policies to alleviate impact? Household Structure Changes in household structure Demographic determinants Social impact 9

10 Concepts Discussion What is family vs. household? What is the traditional households? Nuclear family vs. extended family Family household vs. nonfamily household What kinds of households are there in the US? Which kind of households is the dominant type? U.S. Households, Family household: 66% No family households: 34% Male householder: 15.8% Living alone: 11.9% Female householder: 17.8% Living alone: 14.8%

11 What does this mean? Double Jeopardy Non-Hispanic White African Americans Changes in American households More children are living in single parent families More couples are living together in nontraditional ways More women are working before marriage and outside the home after marriage Families are growing older with delay of marriage and childbearing Team Activities What do you think is the main reason for the change of household structure in the U.S.? A) Higher divorce rate B) Delayed marriage C) Higher rate of childless D) Higher cost for children E) Higher status of women Real Determinants Changing demographic conditions that lead to higher status of women Decline in mortality Decline in fertility Increasing urbanization (rural-urban migration) 11

12 Real Determinants Real Determinants Changing demographic conditions that lead to higher status of women Decline in mortality Decline in fertility Increasing urbanization Higher education Higher labor force participation More individual freedom Changing demographic conditions that lead to higher status of women Decline in mortality Decline in fertility Increasing urbanization Higher education Higher labor force participation More individual freedom New household economics nontraditional households Impact of Changing Household Structure Gender equality? Impact on children? Impact on population? Impact on the economy? China Finds Itself With Labor Shortage Rural-Urban Structure: Urbanization Definition Global pattern of urbanization Urbanization in developing countries Impact, urban problems Definition Definition What is urban? Defining Urban Urban place: a spatial concentration of people whose lives are organized around nonagricultural activities No universal definition Various criteria Inconsistency Defining Urban Conventional criteria: Population size Population density Economic and social organization U.S.: a combination of population density and size Pop size > 2,500 Population density of the core census blocks >1000 persons per square mile Continues areas density > 500 persons per square mile 12

13 Definition U.S. Metropolitan areas: a core area containing a large population nucleus, together with adjacent communities that have a high degree of economic and social integration with that core US Census Bureau MSA: county, core city >50,000 people CMSA: >1 M people (New York-Northern New Jersey-Long Island) PMSA: subarea>1m, strong internal social and economic ties (Long Island's Nassau and Suffolk counties are PMSA of NY CMSA)) Urban agglomeration (UN): no administrative boundaries, >1 M population mega-city (10M+) Urban Transition Urban Transition The reorganization of human society from being predominantly rural and agricultural to being predominantly urban and non-agricultural Urbanization as a multi-dimensional process Economic structural shift of employment from agricultural to nonagricultural sector. An increase share of industries and services in national economy Urbanization Urbanization as a multi-dimensional process Economic Demographic Demographic transition Figure

14 Urbanization A multi-dimensional process Economic Demographic Demographic transition Demographic components Internal rural-urban migration Natural increase in urban population International urban migration Reclassification of places Annexation in Huston Urbanization A multi-dimensional process Economic Demographic Social Spatial Measuring urbanization Level of urbanization: % urban population Rate of urbanization: how fast the place is urbanizing China (and most LDCs) has lower level of urbanization than U.S. but faster rate of urbanization Urbanization A multi-dimensional process Measuring urbanization Urban system/hierarchy Primate city: A disproportionately large leading city holding a central place in the economy of the country Rank-size rule (P i =P 1 /R i ) Team Activity List main trends/patterns in global urbanization Global Pattern Trends in Urbanization, by Region Urban Population Percent An increasingly urban world World Africa Asia Latin America/ Caribbean More Dev eloped Regions Source: United Nations, World Urbanization Prospects: The 2001 Revision(medium scenario), Population Reference Bureau 14

15 Global Pattern An increasingly urban world Higher level, more urbanized places More mega-cities Global Pattern An increasingly urban world More mega-cities Importance of small cities 30% of world pop living in cities <=1 million Importance of Less developed regions 15

16 Percentage of urban population and agglomerations by size class, 2011 Urbanization in Developing Countries The second wave of urbanization is in LDCs It does not really follow the pattern in MDCs Uniqueness: Mismatch between industrialization and urbanization Urbanization in Developing Countries Uniqueness: Mismatch between industrialization and urbanization Higher urbanization, lower industrialization under-urbanization Lower urbanization, higher industrialization over-urbanization (e.g. China) High urban primacy In contrast to the Rank-size rule in developed countries 16

17 WHY? Urbanization in Developing Countries Uniqueness: Mismatch between industrialization and urbanization High urban primacy Reasons Colonialism Export dependency Decline of the rural economy Economic transition from subsistence to capitalist production Urbanization in Developing Countries Uniqueness: Mismatch between industrialization and urbanization High urban primacy Temporary migration High fertility in cities Inequality Between the urban and the rural Among cities Within cities Team Activity What do you think is the most important population related urban issue in the U.S.? Impact of Urbanization Positive impact Urban problems Urbanism as a way of life High density leads to behavioral change Over-urbanization in LDCs Crowding, housing shortage, slums, overburden of infrastructure, lack of clean water Suburbanization/urban sprawl in MDCs NIMBY, BNANA Long commute Land use White flight and residential segregation Edge city, declining downtown/gentrification 17