8.6 Measuring marriages

Marriages are measured in the same way as other population phenomena, i.e. the number of marriages contracted is expressed in proportion to the mean population. The most commonly used index is the crude marriage rate, which is the number of marriages contracted per one thousand in the mean population. Interpretation of the crude marriage rate involves similar problems as the interpretation of other statistics describing population phenomena. The mean population includes large numbers who are not exposed to the risk of marriage.

The prevalence of marriage depends very much on age, and indeed the most accurate measures are provided by various age-specific statistics. Age-specific statistics are calculated separately for men and women because men are some two years older than women when they marry for the first time. Furthermore, statistics describing the marriage rate are often calculated separately according to the number of the marriage.

Age-specific marriage rates are calculated separately for men and women by counting the number of persons in each five-year (or one-year) age group who have married per one thousand same-aged and eligible (unmarried, divorced and widowed) persons in the mean population. These age-specific marriage rates are often counted separately for persons who have married for the first time. In this case the number of unmarried persons will be used as the mean population.

The total marriage rate describes the proportion of the population who marry during their lifetime. This is calculated separately for men and women, although the figure usually quoted is the total marriage rate in women. This statistic is counted by summing up the age-specific marriage rates. The number of women (men) in all age groups rather than the number of unmarried persons is used as the mean population.

The mean age at marriage is calculated on the basis of the mean age of men and women who have married. It is counted separately for persons marrying for the first time, for the second or subsequent time and of course for everyone who has married during the year under study.