DEFINITION OF DEMOGRAPHY

To define demography there need to start with by population. The influence of statistics is immense in demography. As such, population to a demographer refers to an average of people possessing some specified characteristics within a precisely defined area. We can use either geographic or social space or both to demarcate one population from another.

The credit of adding the word Demography to our vocabulary goes to Achillle Guillard. The term has variously been used in economics, geography, sociology, anthropology and other social science. They have defined the term from their own point of view to suit their conveniences. Therefore some definitions are too narrow and some are too broad to include a wide variety of things. Some definitions are as follow:

Demography is a function of fertility, mortality and migration.

                                                                                                   -Gywalli, Damother

The study of the size, composition and the distribution of population is demography.

                                                                                                         -Thomson and Lewis

Demography is the numerical analysis of the state and movement of human population inclusive of census enumerations and registration of vital processes and whatever qualitative analysis can be made of the state and the movement of population on the basis of fundamental census and registration data.

                                                                                                                      -Von Mayor

The mathematical, scientific and statistical study of the size, composition and spatial distribution of the population through the operation of five processes of fertility, mortality, marriage, migration and social mobility its long run goal is to develop theories to explain the events that is charts and compare.

                                                                                                             -Donald J. Bogue

Demography is the study of the size, territorial distribution and composition of the population changes therein and the components of such changes, which may be identified as natality, mortality, territorial movement and social mobility.

                                                                                                      -Hauser and Duncan

Scientific study of human population primary with their size, their structure and their development is demography.

                                                                                         -The Multilingual Dictionary

Demography does not deal with the behavior of individual but only with the aggregates of people or even part therefore the numerical of human population is known as demography.

                                                                                                           -W.G. Barckly

Demography

Statistic and scientific study of population is called Demography. It is a new science in study among other science. Achillle Guillard was the first person who used the term Demography in 1855 in his book Elements de Statistique Humaine on Demography Comparee. The term Demography is derived from two Greek words, Demos, means people and Graphein, to draw or write. Guillard used the term to denote mathematical knowledge of the social, intellectual, physical and ethical aspects of a population.  Demography stands for measurements by statistical methods of various characteristics of human population. Its principle concern is with population size, distribution and growth of population of a region, nation and the world. The constituents of growth of change are births, deaths and migration. Therefore, a demographer's primary concern is with fertility, mortality and population transfer from one region to another. They take keen interest in studying interaction between social, economic and political activities and demography related processes as size, distribution, composition and change in number determined by fertility, mortality and migration.

The demographer study populations with all their characteristics both at a single point and at different points of time. Whereas the former provides valuable information for comparing various population groups spread over space age and sex composition, vital rates, generic composition the latter provides an opportunity to study relation between two population in an area at two points of time, that is those aged x at a time t are survivors of those aged x-n at the time t-n, subject to mortality and migration. This helps projection of population and its composition, changes in birth and death rates and also changes in expectation of life at different ages.

John Graunt was known as founding father of modern demography. Graunt's book Natural and Political Observation Made upon the Bills of Mortality was the first-ever book on experimental and theoretical demography. From the records preserved in churches and cemeteries in London and around, Graunt studied in great details the information recorded for each married and deceased person and analyzed the collected information and tried to estimate, birth, death, marriage, migration rates and their interdependence. Graunt noted that the sex ratio at birth favored male babies. He also noted mortality changes with age. He also observed variations in mortality and causes of mortality with time and space. Based even on utterly inadequate information, Graunt prepared a table for age-specific death rate. This can be regarded as the true ancestor of modern Life table.

William Petty went a step further and tried to relate various population statistics to social, political and economic backdrop. Even with improved techniques of analyze and interpret many population issues. Petty tried to find answer to some such complex issues even though there was no apt technology to support his analysis and research. He tried population projections, and to show how urbanization was related to economic and social structure, to understand population structure and distribution in relation to active age group in the population, he gave considerable thought to problems of unemployment and partial employment and other social problems and tried to estimate gross national productivity. 

POPULATION GROWTH IN ASIA AFTER SECOND WORLD WAR

According to world data sheet 2003, 60.67 percent of the world population lived in Asia. Asia is the house of 75 percent of those living in developing regions. Asia's share to the world population is likely to come down to 58.5 percent in 2050. Six out of 10 most populous countries are in Asia. These countries are China 1304 million, India 1065 million, Indonesia 220 million, Pakistan 154 million Bangladesh 146 million and Japan 128 million.

The population growth rate was 2.0 percent per-year in 1950-55 in this continent and reached a high of 2.4 percent in 1965-70, gradually declining thereafter. The estimated growth rate in 2000-5 is 1.3 percent. Average Crude Death Rate in Asia has reached nine per thousand populations. But Afghanistan the Crude Death Rate is 21 per thousand, death rates in all other countries are below 14. Kuwait and UAE have attained Crude Death Rate 2, probably lowest anywhere in the world. Afghanistan has the highest Crude Birth Rate 47 per thousand in the continent. Yemen's Crude Birth Rate 45 per thousand and few other countries still have exceedingly high birth rate with the result that these countries are still growing at an alarming rate, beyond  3 percent. Both Crude Birth Rate and Crude Death Rate vary considerably between sub-region and between countries in the same-regions. Death rates in most countries have stabilized at a much lower level.

Asia has the second highest current growth rate, only after Africa. Much of the decline in population growth rate in Asia is attributable to drastic reduction of fertility in China. From per year growth rate around 1.8 percent in China, the same in 2000-5 is estimated to have come down to only 0.7. There has been a birth rate reduction by 8-10 points after 1980. Between 1965-70 and 1980-85 the aggressive birth reduction policy in China brought down the per year growth rate from 2.9 to 1.5 percent, nearly a 50 percent reduction just in 20 years. Current growth rate in China is likely to be around 0.5 percent per year.  

Fertility has decline substantially in most of the major Asian countries from seventies in the last century and more countries have joined them since the eighties. Average birth rate has fallen from 28-31 in the eighties to about 21 in 2000-5. Crude Death Rate in the eighties was already in 10-11 brackets. It has dropped by another 3-4 points in the last 20 years. However, mortality under age 5 and IMR are still quite high. By the mid-eighties the life expectancy in many countries reached 60 years. The current life expectancy on average is estimated at 67 years. Japan has the highest expectation of life, 82 years.

Both Young Age Dependency and old Age Dependency in Asia are very close to world average. Population density is highest in the Asian continent per 120/km square. Except Western Asia, the map is almost the same in all sub-regions in this regard. The range of urbanization varies widely. All the countries in Eastern Asian except China have very high urban population, between 57 and 100 percent like Hong Kong. The proportion of urban population is considerably low in Asia. In India, Pakistan and Bangladesh has an average of 31 percent of the population living in urban areas. Bhutan is the only country in the region which has single digit proportion of urban population.  

Malthusian Population Theory

Thomas Robert Malthus was the first person who spoke about problem of population growth. Population Theory was the first theory for population study which was published by Malthus. At that time British government as well as entire European government haughty to expand their colony so they wanted to adequate military force and economy. Therefore, they were towards the aspect of population growth in order to get the both military force and economy. In other hand, many industrial hosts also wanted to expand their industrial activities for enough profit. So they wanted more people in their state for work in industrial field. European learnt William Godwin, Buffon, Mostesque were also aspect of population growth. At that time population growth had been increasing in rapidly as a result there started to decline the facilities of living support things day to day. Therefore there were divided clearly seen two class society poor and rich in that period. Poor class people were being poorer there had started to see lack of food problem. Other side rich class people were being richer and richer. Malthus was studied this situation in nearly and he found out the cause of entire problems was by poor and unemployment and he declared that the control of population growth was the better measure to solve the problem. 

He published his essay on the principle of population in 1798 including the measure solution of population growth and occurring problems. He said that in his essay population growth was harmful. But his that opinion was criticism rapidly at that time. After than, he improved his concept, weakness and deficient on first essay and published next essay "An essay on the principle of population as it affects for the future improvement of society" this essay is known as the complete theory of Malthus.

Two postulates of Malthusian Theory

 First, food is necessary to the existence of men.

Second, the rage between the sexes is necessary and will remain nearly in its present state.

Interpretation of Malthusian Theory:

Population growth rate:

Nature gives the rage for all the living creature for get continues their race or species. So man also not rid from this system, man has as more rage capacity so man highly involve in sexual intercourse. Thus, highly sexual intercourse creates high birth rate because they have more fecundity capacity so giving offspring is increase in geometrical ratio, 1:2:4:8:16:32:64:128 like this and population is double every in 25 years.

Food Growth Rate:

The size of land is limited. Food can not produce as population growth ratio but food is necessary to man for live. So, there starts degradation of land production as a result food production increase arithmetical ratio.

Thus, the geometrical growth ratio of population growth rate as fast leaps the arithmetical growth ratio of food production while increasing them and brings food problem. These problem could not be solved by the human effort if not there would be horrible hazard, disaster events, awful and hindered situation may creates by nature.

Malthus's measure of check for population growth

Malthus said that population growth would be control by human effort which is better, presented the population growth check measure in two ways which are as follow:

Natural checks:

Malthus said that when the population growth is high and imbalance between population and food at that situation to make less in imbalance the nature itself brings flood, landslide, earthquake, cholera, epidemic, lack of nutrition food, scarcity of food for long time, drought that decline and kills man and population become less and being balance between population and food. 

Malthus believed that nature is powerful and it itself can control the population if there is lack of human efforts to control growth of population.

Preventive checks:

According to Malthus the population growth control is more horrible and awful by nature, so human should be active and use artificial checks itself to control population growth. He gave two systems for to control population; a) Moral Restraints, according to this view, to get delay marriage, celibacy, self-control, not to give births are the moral restraints measure it helps to bring down the birth rate. b) Artificial Restraints, according to Malthus, prostitution, abortion and an unshackled intercourse could be a powerful incitement to early attachments. He advised that women to remain unmarried till the age of twenty-eight. He regarded the artificial birth controls as vice or sin.

POPULATION GROWTH AFTER SECOND WORLD

At the beginning of mid-seventies the average world population growth rate started to decline from a highly of 2.1 percent in 1965-70 to about 1.6 percent in 2000. However, even with population growth rate curtailed, the absolute increase every year is still higher than that in the previous year. It is mostly because of the expanding population base. Since 1950 there have added around 2,000 million and still are adding around 75-80 million every year. UNDP estimates that the average annual growth rate between 2003 and 2015 would be around 1.1 percent. Even if this growth is reached, there shall be adding about 700 million by 2010 and another 400 million in the next 5 years. In 1950, about 32 percent of the world population was from the more developed regions in 1995, this came down to about 27 percent and in 2000 their share was down to about 23 percent and then to only 18 percent in 2008. By 2050, the developed county's share is likely to be only 14 percent. Between 1950 and 2000, the population in the developed regions increased by 50 percent while the developing regions increased by 170 percent. Africa's population, currently growing faster than any other major region, is estimated to account for 21 percent of world population by 2050, up from just 9 percent in 1950.

There were 1 billion populations in 1804. After 123 years this population reached 2 billion in 1927. The population growth rate grew in rapidly and world population reached 3 billion in 1960 by the 33 year later from in 1927. After 14 year later from 1960 the world population reached 4 billion in 1974. In 1987 and 1999 world population reached respectively 5 and 6 billion. In the present world population have reached 7 billion.  There is estimated the world population will reach 8 and 9 billion respectively in 2028 and 2054.

Economic Theory of Population

Scientists through many disciplines have contributed generously on issues relating population growth and the well initial stage of people, resource management, industrial development, pollution control and other many more. The economists as a class stand out clearly by the volume they have written on population and have established how modernization, industrial development and above all the quality of life are intimately related to birth rate and population growth in a society.

In the world for a long time is divided between two clusters of nations in one cluster is the nation that have achieved a very commendable control over birth rate thereby bringing the population growth rate to a near stationary condition and the countries in the other cluster still continue with high population growth rate. The first group countries are industrially and economically well ahead of others. They use the most sophisticated technology both in industrial and agricultural production and have a decent standard of living. The countries in the second cluster are not only economically far behind the nations in the first group, their economy is still largely dependent on traditional agriculture and their standard of living is well behind in comparison with the developed countries. Demographic forecasts are that fluctuations will be a dominant feature than a secular trend in future fertility scenario in modern industrial developed population. In less industrially developed population the fertility decline will show a secular trend. It is therefore no wonder that the economists dominate in the debate and discussion on population.

Malthusian Population Theory

Thomas Robert Malthus was the first person who spoke about problem of population growth. Population Theory was the first theory for population study which was published by Malthus. At that time British government as well as entire European government haughty to expand their colony so they wanted to adequate military force and economy. Therefore, they were towards the aspect of population growth in order to get the both military force and economy. In other hand, many industrial hosts also wanted to expand their industrial activities for enough profit. So they wanted more people in their state for work in industrial field. European learnt William Godwin, Buffon, Mostesque were also aspect of population growth. At that time population growth had been increasing in rapidly as a result there started to decline the facilities of living support things day to day. Therefore there were divided clearly seen two class society poor and rich in that period. Poor class people were being poorer there had started to see lack of food problem. Other side rich class people were being richer and richer. Malthus was studied this situation in nearly and he found out the cause of entire problems was by poor and unemployment and he declared that the control of population growth was the better measure to solve the problem. 

Demographic Transition Theory

Demography transition theory is known scientific theory and modern concept in the field of population study. This theory developed on the basis of real and historical events than other theories. This theory developed from the experience of developed industrial western countries but this is important for developing countries as well. Transition of population may call the revolution in population or demography cycle. It is also call the complete expansion describe from high stage to low stage of population. In the high stage showed there was high birth rate and high death rate so population is stable and low stable stage shows the low birth rate and low death rate so population growth is stable.