Definition: Square method
Method used to compute demographic rates of a certain demographic event, e.g. death or giving birth. The numerator consists of all persons who experience that demographic event during a giving calendar year and who had a given age in completed years (age last birthday) at the time of that event. The denominator is the arithmetic mean of the persons who had that age in completed years at the beginning of the calendar year and the number of persons who had that age at the end of that calendar year.
Eurostat, "Demographic statistics: Definitions and methods of collection in 31 European countries (2003 Edition)", Luxembourg, 2003