1957 - United Nations Statistics Division

advisable to calculate this index annually, even though
the bases for the calculation might not always be as firm
as would be desired. Despite its limitations, set forth
below, it does give an indication of over-all growth or
decline. The rate of natural increase, which was considered
as an alternative, is available for fewer areas and
may be calculated from data in Tables 6 and 8.
As noted above, Table I is the only table in the Yearbook
which shows geographic units classified according to
their administrative status, i.e., sovereign countries, territories,
colonies, protectorates, dependencies, condominiums,
and those under military government. In so far as
possible, this classification reflects the situation as of I
November 1957. It, together with the extensive footnotes
which describe the boundaries of the areas in detail not
found elsewhere in the Yearbook, makes this the reference
table of the volume in respect of territorial composition.
It is also the reference for terminology in English and
French, incorporating as it does the most recent official
forms of country names. 9
Unless otherwise indicated, both census and estimates
relate to the modified present-in-area population as
described on p. 15. In so far as possible, the figures presented
in the census columns of Table 1 are confined to
the population actually enumerated in these areas at the
most recent "true" census,lO whether this enumeration
was complete or partial in geographic and ethnic coverage
and irrespective of the degree of underenumeration. Official
estimates for excluded groups and for underenumeration
are shown in footnotes when known; the results of
re-counts which were considered to be part of the original
enumeration are not shown-as, for example, the 0.86%
underenumeration found among 6,878 persons in 135
districts in Costa Rica where completeness of enumeration
was suspect. ll
The inclusion in Table I of all "true" censuses,
whether national in scope or limited to some segment of
the population, provides a survey of census-taking activity
throughout the world. It makes possible the identification
of countries which have never carried out any type of true
census, those which have taken a census of limited scope
in terms of persons enumerated, and those which have
taken a true national census.
Unless otherwise specified, estimates refer to the midyear,
i.e., to the population at 1 July of the relevant year.
However, in the absence of a midyear estimate, a mean of
two successive end-year (31 December) estimates may have
been used. No distinction is made between these two types
of midyear estimates, on the assumption that the difference
involved is negligible. When an official estimate was
not available for a year in which a census had been taken,
the results of the enumeration are shown in the estimates
column, but in italics to distinguish them from the midyear
estimate.
In a few cases where neither an enumerated population
nor an official estimate was available, unofficial estimates
have been shown for 1953 and 1956 in order to provide
an idea of the current size of the population in every part
9 See p. 14.
10 In general, a "true" census has been understood to mean one
conducted with individual or family schedules-whether on a sample
basis or 100% coverage.
11 Direcci6n General de Estadistica y Censos. Censo de Poblaci6n
de Costa Rica del 22 de mayo de 1950, San Jose, 1953, p. 2-3.
of the world. Such unofficial estimates are identified in the
table by the symbol "x" or a footnote specifying their
source.
The type-of-estimate codes, the construction of which
was described in detail on p. 16, are induded in this table.
In accordance with practice introduced in the 1956 Demographic
Yearbook, codes are shown both for official and
unofficial 1956 estimates. Together with information on
underenumeration, the code furnishes the basis for fairly
precise evaluation of the 1956 estimates of populationwherever
they appear. An explanation of the components
of the code is given on p. 17.
The area figures, given in square kilometres, relate to
the total area of the specified geographic units, including
inland water as well as such uninhabited or uninhabitable
stretches of land as may lie within their boundaries.
Wholly uninhabited areas, such as the polar regions and
a few small islands, are not always listed in the table and
are excluded from the statistics. Area estimates are official
unless marked with the symbol "x." Areas reported in
square miles have been converted to square kilometres
using the factor 2.589998.
Coverage: The stub of Table 1 includes 266 identifiable
geographic units, data for which can be summed to give
continental and world totals. It is, therefore, the most
complete of any table in the Yearbook.
In so far as possible, an attempt is made in this table to
show the component parts of every collective area. As in
previous issues, data for the component geographic units
are here distinguished by being set in smaller-type size.
Where it is not feasible or convenient to show the components
separately. footnotes explain the inclusions.
Per cent rate of growth: The annual per cent rate of
change in population size between 1953 and 1956 has
been computed to one decimal, rounded, from data in
the table, using the following formula:
P l = Po (1 + r)t X 100
where Po is the population in 1953,
P l is the population in 1956,
t is 3 (years between 1953 and 1956), and
r is the annual rate of change.
Although estimates in Table 1 appear only in thousands,
figures in unit digits were used whenever available
for the computation of rates. In some cases, however,
available estimates were only those rounded to the nearest
thousand. When the number of significant digits was so
few as to cause the possible error to reach -t- 0.5, the resultant
rate is so footnoted. Special mention must be made
of the rates for Indonesia, Japan, Korea, and Macau. In
these cases, although one of the base figures appeared
rounded to the nearest million, or 100,000 thousand, it
was assumed that the number of significant digits in the
other component governed both and the rates were computed
accordingly. No rates are computed for populations
of magnitudes less than 50,000 because chance variation
alone would in these cases amount to at least 0.5%. A
footnote identifies these in the column. Likewise, no rate
is computed where the 1953 and 1956 estimates in thousands
are identical, even though unit digits might show a
distinction. In these cases, a symbol (.) is used to signify
that a rate is not applicable.
19
Computation of density: Density is the number of persons
in the 1956 total population per square kilometre of total