Marriage in most OECD member countries has been in decline since at least the 1970s, although there are large variations across countries with marriage rates being highest in the United States and lowest in Nordic countries. Cohabitation remains relatively rare in the United States and southern European countries while the “Nordic family model”, of low marriage and high cohabitation rates, together with high non-marital fertility is becoming increasingly common in Canada, France and the United Kingdom. In southern Europe and Japan, both fertility and marriage rates are very low, as is non-marital fertility and cohabitation (Lundberg and Poliak, 2007). While single people are more likely to be poor than those in couples (as a result of economies of scale in consumption among couples) cohabitation too has been linked to higher rates of poverty than those among married couples.