This average figure concealed important differences between sub-groups, in terms of gender (female 3.6 per cent; male 2.5 per cent), education (those with university degrees 5.4 per cent; those with minimal educational qualifications 1.4 per cent), race (whites 3.4 per cent; blacks 1.4 per cent) and marital
status (separated or divorced 6.8 per cent; married 2.7 per cent).