POPULATION DATA

-The U.N. recommends that a census is carried out every 10 years, although it prefers censuses to take place every 5 years.

-In MEDCs, the census requires heads of households to complete a form answering questions about all members of their household. The questions are related to age, sex, marital status, birthplace, ethnic background, education and economic activity.

-It is a static measure as it takes a snapshot of the population on a given day.

-In MEDCs, and in some LEDCs, there is a legal requirement to register significant events such as all births including stillbirths, adoptions, marriages and civil partnerships, and deaths.

-Vital registration in most of the LEDCs is inadequate and those people who do register may not be representative of the whole population, e.g. they tend to be wealthier and better educated. 149 million children in the world without birth certificates means that they can be exploited by people for underage working.

-The term migration is frequently used to describe any kind of movement by people, but most demographers agree that its use should be restricted to moves which involve a permanent change of residence.

-The U.N. constitution defines “permanent” as a change of residence which lasts more than 1 year. It does not include temporary movements such as pastoral nomadism, seasonal movement of labour, commuting to work and tourism.

-Emmigration is the departure of a person from one country to live permanently in another. This person is called an emigrant.

-Immigration is the entrance of a person into a country with the aim of living there permanently. This person is called an immigrant.

-Literacy levels - Poor education rates in LEDCs = people cant read or write therefore be unable to complete a written census form.

-Lifestyles - Nomadic tribes and families can be difficult to find - may migrate across international bounderies.

-Sight ad special needs - Difficult to fill in the form

-Cost - Some LEDCs do not have the money to spend on census collection.

-Mapping inaccuracies - Households may be left out.

-Language barries - e.g in Camaroon 30+ languages spoken.

-Lack of reference - Some people not aware of what age they are.

-Confidentiality issues - May not want the government to be aware on them so refuse to fill in the form.

-Originally information was collected by door-to-door collectors, but since 1841 it has been a form to be collected by the head of the household. 

• Population - knowing how many people live in an area helps government allocate funding.
• Education - helps to plan location of education services for the future.
• Housing - can be better planned if authorities know where the demand is.
• Employment - info can be used to plan jobs and training needs.
• Transport- helps government understand pressures on transport system and improve public transport.

Measures of fertility -
Crude birth rate - number of births per thousand of the population per year.
   -Does not take into account age or gender - inaccurate.

Total fertility rate - average number of children a woman will have during her reproductive years, assuming she will live to the end of her reproductive life.

Measures of mortality - 
Crude death rate - number of deaths per thousand of the population per year
   -Takes no account of age of death.

Infant mortality rate - number of deaths per thousand children in the first year of life.

Stage 1 - High stationary: High birth rates and death rates. Infant mortality in high and life expectancy is low. Population totals do not vary greatly. (e.g UK before 1750 due to poor social and economic conditions)

Stage 2 - Early expanding: High birth rate but death rate falls so total population increases. (e.g UK between 1750-1850 as basic sanitation and health care improved. Medical invancements were made and vaccinations against infectious diseases impacted on death rates. Improvements in agriculture and more employment opportunities. Birth rates still high due to lack of birth control and family planning, need for children to work.)

Stage 3 - Late expanding: Death rates fall but gradually stabalises as population begin to age. Brith rates fall but population continues to increase because of youthful population structure. (e.g UK throughout the 19th century death rate continued to fall due to social and economic conditions improving further. Life was improving in working classes which saw a fall in birth rate as families werent only having children to work.

Stage 4 - Low stationary: Occasional spikes in birth rate, e.g post second World War baby boom, overall population stabilises. Life expectancy increases and most common cause of death is ageing (ie dementia, heart attack). (e.g UK in 1950)

Stage 5 - Decline: Death rate exceeds the birth rate. Low birth rate due to woman focusing on career and not having babies. (e.g Germany)

Stage 1 - Pre-transition stage - Death rates high, common causes of death of small pox, measles and influenza. Many are caused by environmental issues, diet, hygiene and lifestyle. (exogenetic, not related to genetics)

Stage 2 - The receding pandemic - Death rates fall rapidly as infectious deseases are controlled. (In Britain this occured from the nineteenth century onwards). There was significant developements in medicine and vaccinations. Greater understanding of how diseases are spread.

Stage 3 - The age of degenerative and man made diseases - People die from degenerative diseases or endogenetic diseases of elderly e.g alzheimers disease, as well as diseases of affluence e.g heart attack, strokes and cancers.