Page 40 - NIIÊN GIÁM THỐNG KÊ TỈNH HƯNG YÊN 2022

Formula:
B - D
NIR = × 1000
P tb
Where:
NIR: Natural Increase Rate of population;
B: Total number of live births in the reference period;
D: Total number of deaths in the reference period;

P tb: Average population in the reference period.
Growth rate of population (growth rate) reflects the increase/decrease of
the population in reference period due to natural increase and net-migration.
Growth rate of population is expressed as a percentage or per mille.
In-migration rate are the number of people from different territorial
units (out-migration place) in-migrate to a territorial unit in the reference
period (usually a calendar year) on an average per 1,000 population of that
territorial unit (in-migration place).
Formula:

I
IR (‰) = × 1000
P tb
Where:
IR: In-migration rate;

I: Number of in-migrants in 12 months prior to the reference period;
P tb: Average population in the reference period.
Out-migration rate reflects the number out-migrants of a territorial unit
in the reference period on average per 1,000 population of that territorial unit.

Formula:
O
OR (‰) = × 1000
P tb
Where:
OR: Out-migration rate;
O: Number of out-migrants in 12 months prior to the reference period;
P tb: Population up to the reference time-point.

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