The population of a country supports its sustainable development. But the population continues to decline in many countries.

It is because young people give up marriage and they want to have a few or no children even after they are married.

The continued decline in birth rates has resulted in an abnormal population structure.

Countries with a relatively small number of young people and a large number of the elderly in the whole population, villages in which no children were born for several years and schools with no new students increase in number. Rapid population reduction turns many villages and small towns into “desolate towns of ghosts”.

Such an expression as "population annihilation crisis" has been coined and is widely used now.

The population in the seven large cities in the United States has been reduced by more than half as against 1950. Detroit has become one of the five big cities that are likely to disappear from the globe in the future due to the severe population loss.

The Italian bureau of statistics said that the country's population is expected to decrease by 22% in the coming 55 years and particularly the residents of the southern region will radically decrease in number.

In Poland 252 000 children were born last year, a decrease by over 20 000 as against the previous year. The number of births has reportedly reached a record low since World War II.

Over the past several decades the birth rates have been fairly low in most European countries.

Reportedly, the population of Europe is expected to decline continuously till 2100 and it is especially serious in Central and Southern Europe including Poland and Italy.

According to the Ministry of Health, Welfare and Labour of Japan, the number of children born in the period from January to November last year dropped by 5.1 percent over the same period of the year before. It has become a tendency to live single in the country.

According to estimates, the population will be reduced by nearly 800 000 annually in this country till 2070, which means that it will decline by half in the early next century.

The UN Population Fund expressed deep concern over the falling birth rates in many countries in its report on the world population published in June. Quoting the results of a population survey conducted in 14 countries, which make up a third of the world population, the report warned that a worldwide population-related crisis may arise in the future.

The population loss has a great negative impact on the economic development of the countries concerned and causes many social problems.

Experts recommend that all countries adopt and carry out policies to cope with the population change actively and effectively and conduct various forms of activities to address the population reduction crisis.