Single mothers are made up of two major groups: one consists of mothers with children from a previous marriage, and the other consists of mothers who have never been married.22 There is also a small group of mothers who are married but whose spouses are not living in the household. In the past five decades, the share of never married mothers among all families with children has increased from less than 1% to 11%. The share of mothers who are divorced, separated or widowed increased in the 1960s and 1970s and has remained relatively stable since 1980, hovering around 12% to 13% in the past three decades.