Page 46 - môc lôc

out-migrants of a territorial unit on average per 1,000 population of that
territorial unit.
Formula:
I - O
NR (‰) = × 1000
Ptb
Where:

NR: Net-migration rate;
I: Number of in-migrants in 12 months prior to the reference period;
O: Number of out-migrants in 12 months prior to the reference period;
Ptb: Population up to the reference time-point.

Or: NR = IR - OR
Where:
NR: Net-migration rate;

IR: In-migration rate;
OR: Out-migration rate.
Life expectancy at birth reflects the prospect of a newborn could live
for how many years if the current mortality model is maintained, this is the
key statistical indicator of the Life table.
T
e = 0
0
l 0

Where:
e0: Life expectancy at birth (unit: year);

T0: Total number of years of the newborns in the Life table who will
continue to live;
l0: Number of persons who live to the age of 0 of the Life table (the set
of original newborns is observed).

Life expectancy at birth is one of the integrated indicators calculated
from the Life table.

The Life table is a statistical table that includes the indicators showing
the viability of population moving from one age to the next and the mortality
of the population at different ages. The Life table shows that from an initial
set of the births (on the same cohort), there will be how many persons who
will live to 1 year, 2 years,..., 100 years,...; among them, there are how many

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