Bulgaria is in a state of demographic crisis. It has had negative population growth since the early 1990s, when the economic collapse caused a long-lasting emigration wave. Some 937,000 to 1,200,000 people—mostly young adults—left the country by 2005. The majority of children are born to unmarried women. Furthermore, a third of all households consist of only one person and 75.5% of families do not have children under the age of 16. The resulting birth rates are among the lowest in the world while death rates are among the highest.