Page 57 - Niên giám

reference period on average per 1,000 population of that territorial unit (in-
migration place).

I
IR   1000
P

Where:

IR: In-migration rate;
I: Number of in-migrants in the reference period;

P: Population up to the reference time-point.
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.

O
OR   1000
P

Where:
OR: Out-migration rate;

O: Number of out-migrants in the reference period;

P: Population up to the reference time-point.
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.

I  O
NR   1000
P
Where:

NR: Net-migration rate;

I: Number of in-migrants in the reference period;
O: Number of out-migrants in the reference period;
P: Population up to the reference time-point.

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