Net reproduction rate

The net reproduction rate is a measure used in demography . It indicates how many daughters a newborn girl would have on average in the course of her life if the current age-specific (and women-related) birth and death rates were valid for the entire period up to the end of her fertile phase of life.

It thus estimates the strength of the daughter generation relative to the mother generation under the currently prevailing conditions and is consequently a measure of the reproductive power of the population. If the value is below 1, one must assume a long-term population decline (excluding migration ) , unless rising birth rates and / or falling death rates counteract this; conversely at a value above 1 of a population growth . A value close to 1 corresponds to a numerically unchanged or stable population.

The speed of growth or decline cannot generally be quantified using the net reproduction rate, because the age of the mothers at birth and life expectancy beyond the fertile phase also play an important role.

The net reproduction rate is determined by multiplying the age-specific fertility rates by the proportion of girls in births and the proportion of women who reach this age group, and then adding them up and dividing by 1,000.

Gross reproduction rate

The gross reproduction rate differs from the net reproduction rate in that it does not take mortality into account, i.e. it is assumed that every girl survives until the end of childbearing age. It can be useful as an upper limit if, for example, it is expected that high child mortality will decrease radically in the near future. However, the assumption of constant fertility rates will usually not be particularly realistic.

"Mother rate"

The GDR operated a birth promotion policy . The aim was to encourage women of childbearing age or couples to have a child or children

• despite the difficulties in the GDR shortage economy and
• although mothers were expected to be employed.

(see also women's and family policy in the GDR , women's work ). The success of this policy was measured, among other things, by what was then known as the “mother's rate”. It was sometimes over 90 percent.

Net reproduction rate worldwide

The following list gives an overview of the net reproduction rate in various countries in the period from 2010 to 2015 according to figures from the United Nations . Of all states and territories, Niger had the highest net reproduction rate (2.98 daughters per woman) and Taiwan the lowest (0.52 daughters per woman).

country	Net reproduction rate (daughters per woman)
Niger	2.981
Democratic Republic of Congo	2.579
Tanzania	2,296
Afghanistan	2.233
Nigeria	2.117
Ethiopia	2.004
Kenya	1,834
Pakistan	1,590
Egypt	1,582
Philippines	1.417
Indonesia	1.137
South Africa	1.126
Mexico	1.085
India	1.064
Bangladesh	1.022
Turkey	1,000
France	0.958
Sweden	0.912
Colombia	0.912
Australia	0.908
United Kingdom	0.908
United States	0.904
Vietnam	0.899
Belgium	0.861
Brazil	0.846
Netherlands	0.836
Iran	0.829
Russia	0.807
Canada	0.775
Switzerland	0.738
People's Republic of China	0.726
Thailand	0.726
Austria	0.699
Germany	0.688
Italy	0.687
Japan	0.680
Poland	0.643
Spain	0.639
South Korea	0.590
Taiwan	0.523
world	1.102

Individual evidence

1. ↑ Tilman Meyer: The demographic change (page 272 f .; PDF; 79 kB)
2. ↑ World Population Prospects - Population Division - United Nations. Retrieved June 2, 2018 . 

Web links

• UN database (English)

See also

• total fertility rate