1957 - United Nations Statistics Division

CHAPTER I. FACTORS IN DECLINING MORTALITY
The reduction achieved in mortality during the last
several decades is by now a well-known phenomenon. So
far as can be determined by available statistics, these
trends have been world-wide in scope. Moreover, it appears
that the dramatic declines in the death rate which
some of the so-called "underdeveloped areas" have experienced
have no precedent in the history of mortality
among the countries of the world which now enjoy the
lowest rates. In view of these facts, it would appear useful
to explore the geographic differentials in the observed
decline, as well as those observed in characteristics such
as sex, age, and cause of death.
WORLD DEMOGRAPHIC SITUATION
Since the effects of the world-wide declines in mortality
are reflected in the current demographic status of the
world, it would be advantageous to begin the differential
analysis with a review of the present situation.
On a world basis, only the crudest indices can be
assembled. These include an estimate of total population
and of the rate of population growth the world is experiencing
as a result of the current level of national birth
and death rates. These elements, which are set forth in
Table A, indicate that at the mid-point of 1956, the
world's population was approximately 2,737 million­
55% of whom live in Asia, 15% in Europe, 9% in North
America, 8% in Africa, 7% in the USSR, 5% in South
America, and less than 1% in Oceania.
The population of the world has increased since mid­
1955 by about 47 million inhabitants. This unprecedented
increase has been brought about by an average annual
birth rate of 34 and a corresponding death rate of 18,
both estimated from data available for the period 1952­
1956. It must be emphasized that neither of these rates
is intended to be a precise measure of the true levels of
natality or mortality throughout the world. They are
simply attempts to derive universal working estimates
from a study of the range of registered rates and such
official estimates of natality and mortality as may have
been made from sample surveys, studies of census returns,
and the like, and the correlation of these with the annual
per cent rates of population increase based on official
population statistics. To account for discrepancies between
population increase rates and natural increase
rates, emigration movements have been assumed for East
Asia and Southern Europe and immigration for South
America, South West Asia, and Oceania. Lacking in
accuracy, these rates nevertheless do exemplify the wide
1
gap between the crude birth and death rates, the size of
which is responsible for the current increment in the
population of the world.
Despite the fact that the method of estimation is the
same as that employed in constructing the average rates
for 1951-55 presented in Chapter I of the 1956 Demographic
Yearbook, the two sets are not comparable. Each
series was based on the data available at the time the
rates were estimated and, in constructing the estimates
for 1952-56, advantage was taken of much new information
- especially for Africa.
It will be noted that in terms of geographic regions, the
Tabl eA. Population, 1956; and annual average birth, death
and population growth rates, by regions, 1952-56.
(Rates are annual overages for 1952-56. Birth and death rates are per
1,000 population; population growth is the per cent rate, calculated by compound
interest formula.)
Popula- Population
Death tian
\Vorld and regions a midyear Birth rates growth
1956 rates rates
(millions) (%)
World •••••.••••••••••••••••• 2737 34 18 1.6
AFRICA:
Northern Africa•••••••••••••. 72 42 28 1.7
Tropical and Southern Africa ••• 148 50 33 1.8
AMERICA:
Nothern America ••••••••••••• 186 b 25 b9 1.7
Middle America ••••••••••••• 60 42 16 2.7
South America............... 129 39 17 02.4
ASIA:
South West Asia ••••••••••••• 73 42 22 02.5
South Central Asia .••.••••••• 506 40 27 1.4
South East Asia •••••••••••••• 190 44 28 1.8
East Asia •••.•••••••••.•••.• 745 b 35 b16 01.6
EUROPE:
Northern and Western Europe •• 138 b 18 b 11 0.6
Central Europe .••••••••••••• 135 b19 b 11 0.9
Southern Europe ••••••••••••. 139 b 21 b 10 00.9
OCEANIA.••••••••••••••••••• 15.1 b 25 b9 02.3
USSR........................ d 200 b 26 b9 ...
a The countries and territories included in each region are set forth on p. 20.
b Based on recorded statistics.
C This rate reflects the combined effect of natural increase and migration.
d For 1 April.
1952-56 world average birth rate of 34 per 1,000 population
represents a range of 32 points, from a low of 18
in Northern and Western Europe to a high of 50 in the