Page 41 - NIIÊN GIÁM THỐNG KÊ TỈNH HƯNG YÊN 2022

Net-migration rate reflects the status of in-migration and out-
migration of population into/out from a territorial unit in the reference
period. It is the difference between number of in-migrants and number of
out-migrants of a territorial unit on average per 1,000 population of that
territorial unit.

Formula:

I - O
NR (‰) = × 1000
P tb

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;
P tb: 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:

e 0: Life expectancy at birth (unit: year);
T 0: Total number of years of the newborns in the Life table who will
continue to live;
l 0: 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.

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