Crude birth rate

Ratio (expressed in per thousand inhabitants) of the number of live births of the year to the average total population of the year (sum, divided by 2, of the population on 1 January and that on 31 December of the year).该比率以每千人口（per thousand inhabitants）为计量基准，为当年活产总数与当年年平均总人口数的比值；其中年平均总人口数指当年1月1日与12月31日的人口数之和除以2所得的数值。