• Data reference period
• Place of residence (NUTS - 2002)

• REFERENCE PERIOD:  The length of time for which data are collected, e.g. a specific day, month or year.
• RESIDENT POPULATION:  The persons who regardless of the fact that at the moment of observation ' 0:00 a.m. of the reference day ' are present or absent in a given housing unit, this unit being where they live during most of the year with their family, or where they have all or most of their belongings.
• WORKING AGE POPULATION RENEWAL RATIO:  The ratio between the population that is potentially entering and that which is leaving the labour market, normally defined as the quotient between the number of people aged between 20 and 29 years and the number of people aged between 55 and 64.

RRPA = [(P(20,29)/ P(55,64)]*10^n;

P(20,29)=Population aged between 20 and 29 years old ;
P(55,64)=Population aged between 55 and 64 years old;