...{{TextTerm|characteristics|6|131|2|IndexEntry=characteristic}} (i.e. sex, marital status, etc.). Where data are classified with respect to several variables ...2|IndexEntry=indicator}} of a complex situation; thus the infant mortality rate is sometimes used as an indicator of the health status of a population.

...er 1,000 women of childbearing age, e.g., 15 to 49, is used as an index of fertility when reliable birth statistics are not available. ...The denominator of the marital and non-marital birth rate is sometimes the total population.}}