The 2016 census of Ireland was held on Sunday, 24 April 2016. It was organised by the Central Statistics Office (CSO) and reported a total population of 4,761,865, or a 3.8% increase since the prior 2011 census. This was the lowest recorded population growth rate since the 1991 census, with the decline in population growth rates attributed to both lower birth rates and lower net migration. The census results were released gradually between April and December 2017 in a series of reports organised either as summaries or in-depth results of specific themes, like age, ethnicity, or religion.