Demographic Analysis: Rates, Factors, and Population Trends
Demography: The Study of Human Population
Demography is the scientific study of human population. Demographers use a number of demographic rates to measure population. By comparing all these rates, they can analyse population growth and trends as well as its present-day characteristics.
Key Demographic Rates
- The birth rate is the number of births per 1,000 people in an area over a year. Formula: (Annual births / Total population) x 1000
- The fertility rate is the average number of babies born to women between the ages of 15 and 49. Formula: (Annual live births / Women aged 15-49) x 1000
- The mortality rate is the number of deaths per 1,000 people in an area over a year. Formula: (Annual deaths / Total population) x 1000
- The infant mortality rate is the number of deaths of children under one year of age per 1,000 live births. Formula: (Deaths of children under 12 months / Total of annual births) x 1000
- Rate of natural increase is calculated by subtracting the mortality rate from the birth rate.
- Net migration rate is the difference between the number of emigrants and immigrants per 1,000 people in an area over a year. Formula: (Immigration – emigration / Total population) x 1000
- Rate of population growth measures how fast a population’s size is changing. It is the number of people added to (or subtracted from) a population in a year due to natural increase and net migration. Formula: Natural increase + net migration
- Population density is the total population of a territory divided by its surface area. Formula: Total population / Area (in km2)
Factors Influencing Population Density
Physical Factors
Natural environments with favourable conditions usually have high population densities. These conditions include abundant water, a temperate climate, low fertile land, and mineral resources. Likewise, regions with little water or extreme temperatures are less densely populated. Certain parts of the world such as the great river valleys of the Nile and the Ganges, or the east coast of China have been settled for thousands of years because of physical factors.
Human Factors
Today, population density usually reflects economic activity. A region with considerable industrial, mining or agricultural production is likely to be densely populated. In recent centuries, cities have attracted large populations by offering job opportunities and becoming the centres of transport networks.
Ageing Population
A low fertility rate and high life expectancy are the main causes of Europe’s ageing population: more than 16% are over 65 years of age. Its working age population decreases every year and its dependent population grows.
High Life Expectancy
Medical advances and improvements in nutrition and living standards mean that people live longer.
Low Fertility and Birth Rates
Many women work and often wait before they have children.
Population Growth
Population growth increased during the first half of the 20th century because the birth rate was higher than the mortality rate. However, the impact of the great influenza epidemic of 1918, the Civil War and the post-war years, all prevented population growth from rising more rapidly.
Population Distribution
Spanish population is distributed very unevenly across its territory. These differences are mainly due to the historical development of the country. Until the 17th century, Spain’s inland areas were highly populated. Since the 18th century, economic development on the coast has increasingly attracted immigrants from the centre of the peninsula.
Population Density Map
Highest Density: Brussels, Netherlands, South United States
Lowest Density: Spain, France, Lithuania
Data Collection
The census is the official count of how many people live in a country, city, village…It takes place every year. The municipal register contains records of the number of inhabitants for each municipality and it is updated every year.
Demographic Transition in Spain
Old demographic regime, Spanish flu, increase population 1920, civil war and post-war period, baby boom, population stagnation (recent years).