Aging Population
The world's population is growing at a rate of a little more than 1% per year.
However, not all segments of the population are growing at the same rate.
This graph shows the rate of growth have 3 different groups:children,adults and the elderly.
As you can see, while the population of children is fairly constant, the elderly population is increasing at a fastest rate.
This is due the very low birth rates in developed countries and birth rates declined in most developing countries.
As a result of this trends, the world's population is aging.
Between 2015 and 2050, the percentage of world's population over 60 is expected to nearly double.
In 2015 there were 900 million people over 60, in 2050 the number should be around 2 billion.
Aging populations are becoming a huge problem in many countries, especially developing countries.
It used to be that many elderly people lived with their family and helped take care of the next generation.
They had a place to stay and people to help take care of them when they needed assistance.
Now however, many elderly people, or senior citizens, are left on their own.
This is partly the result of people having fewer children and also because of massive urbanization.
Young and middle-aged adults have left the rural areas for economic opportunities only available in large urban centers.
As a result, there is no one to care for the elderly who are left behind to live on their own.
This is especially true in developing countries.
With an aging population, health problems become a growing concern.
Some of the leading conditions that accompany aging include vision problems, hearing loss, diabetes and dementia such as Alzheimer's disease.
These problems can lead to disabilities that make it difficult to live without assistance.
With diseases such as Alzheimer's,people lose their memory and unable to recognize their own children.
Worldwide more than 46% of people age 60 and over have disabilities.
Getting meals and medical care for example become both expensive and difficult.
As a result, the costs of providing services to the sick and disabled can become a huge problem.
Repeat
Different segments of the population are growing at different rates.
Memory loss is one example of a disability.
With an aging population there will be more sick and disabled people to care for.
Massive urbanization occurs when many people move from rural areas to large urban centers.
A disabled person is someone who generally needs some kind of living assistance.
Elderly people are often referred to as senior citizens.
Dependency Ratio
In economics, the dependency ratio shows the relationship between the number of people not in the labor force and those in the labor force.
Those not in the labor force are the dependent part of the population.
Those in the labor force are the productive part of the population.
A high dependency ratio means that there are fewer working people to support health,social security and education services which are used by the dependent sectors of a population.
This number is calculated by adding together the total number of young and old people and dividing that number by the number of working age people.
Sometimes the dependency ratio is presented in two parts.
One part focus on the ratio between children and working age population.
This is the dependency ratio for the young.
The others the ratio between the elderly and working age population which is the dependency ratio for the old.
Here are some dependency ratios for the old in 5 countries: China,India,Japan,the US and the U.K.
It shows the ratios at 3 different points of time:2000,2015 and 2050.
Note that the greatest percentage change from 2015 to 2050 is for China.
The dependency ratio nearly triples,from 13.1 to 39.
The other countries show gains, but as a percentage increase, they are less.
In Japan the ratio increases from 43.6 to 71.8, which is less than double.
The life expectancy for Japan in 2050 is predicted to be 93, which is the highest of these countries.
A high life expectancy obviously increases the dependency ratio.
And note that the dependency ratio ignores the fact that those counted in elderly segment of the population are not necessarily dependent.
An increasing proportion of them are working,and many of those in the working age segment may not be working.
So this way of calculating the dependency ratio in the country can be misleading.
By pointing this out,we can see the danger of using such numbers to make policy without understanding how they are calculated.
In the end, details are important.
Repeat
In percentage terms,China's dependency ratio is expected to nearly triple.
The unemployment rate isn't taken into account, so the dependency ratio doesn't change.