One-Parent Families Mr. Race asked the Secretary of State for Social Services what is his most recent estimate of the number of one-parent families; and what are the assumptions behind this estimate. Mrs. Chalker An assessment of the available evidence suggests a figure of the order of 825,000 for the number of one-parent families in Great Britain at mid 1978. This estimate draws on evidence from a number of sources to bring up to date estimates of the number of one-parent families derived from the 1971 census of population. Among these sources are annual statistics about numbers of divorces involving dependent children, admnistrative statistics on numbers of one-parent families in receipt of supplementary benefit and analyses of information about families collected in the general household survey. The hon. Member may find it helpful to refer to the discussion of the problems of definition which are involved and the discussion of the sources of data and methods used in compiling estimates which was published in the Autumn 1978 issue of " Population Trends", the quarterly journal of the Office of Population Censuses and Surveys.