District health boards (DHBs) in New Zealand are organisations established by the New Zealand Public Health and Disability Act 2000, responsible for ensuring the provision of health and disability services to populations within a defined geographical area. They have existed since 1 January 2001 when the Act came into force. There are 20 DHBs (15 in the North Island and 5 in the South Island). From their creation until 1 May 2010, there were 21 DHBs. At that date, Otago DHB and Southland DHB amalgamated their boards to form the new Southern DHB. DHBs receive public funding from the Ministry of Health on behalf of the Crown, based on a formula which takes into account the total number, age, socioeconomic status and ethnic mix of their population.