Having examined at great length the nature of the population control programme with its various components introduced at different times in response to prevailing demographic trends and economic conditions, we will now proceed to investigate the levels and trends in fertility during the post-war period up to 1977, paying particular attention to the more interesting developments that had taken place in the 1970s. In this task we have been greatly assisted by the availability of accurate and comprehensive birth statistics generated from the efficient vital registration system in Singapore. For one thing, the coverage of birth statistics is known to have attained near 100 per cent completeness, and from 1953, these data have been made available according to the date of occurrence of live-births. Data on live-births by age of mother have been made available progressively in greater detail since 1943, with birth order statistics first published in 1967.

Our study of fertility levels and trends is based largely on the total fertility rate though the crude birth rate is also used. The crude birth rate, defined as the total number of live-births occurring during one calendar year per thousand population living in the middle of the same year, is easy to compute and understand, but it suffers from some inherent defects. It is distorted by differences in population structure and is not suited for assessing fertility differences over time or among various groups of the population. The total fertility rate is the average number of children that would be born per woman in a group of women if all women survived to the end of their reproductive years and bore children at each age in accordance with the age-specific fertility schedule for women of various ages. Computation of this rate requires data on the number of births during the year tabulated by the age of the mother and on the total female population at mid-year of the same year by five-year age groups. The total fertility rate, which is independent of the effect of the sex and age composition of the population, is a satisfactory measure for analysing fertility trends and differentials.