Until April 2011, responsibility for estimating the population of Scotland, as well as recording births, deaths and marriages, was overseen by the General Register Office for Scotland (GROS), headed by the Registrar-General for Scotland. From 1 April 2011 onwards, the GROS merged with the National Archives of Scotland to become the National Records of Scotland. The new organisation is still required under the terms of the Registration of Births, Deaths and Marriages (Scotland) Act 1966, to present a Registrar-General's annual report of demographic trends to Scottish Ministers. (Prior to devolution it was to the Secretary of State for Scotland). In conjunction with the rest of the United Kingdom, the National Records for Scotland is also responsible for conducting a decadal census of population. The most recent one took place in March 2012, with the next due to take place in 2022.