[http://www.cso.ie/census for post 1821 figures 1653 and 1659 figures from Civil Survey Census of those years Paper of Mr Hardinge to Royal Irish Academy 14 March 1865 For a discussion on the accuracy of pre-famine census returns see JJ Lee "On the accuracy of the pre-famine Irish censuses" in Irish Population Economy and Society edited by JM Goldstrom and LA Clarkson (1981) p54 in and also New Developments in Irish Population History 1700–1850 by Joel Mokyr and Cormac Ó Gráda in The Economic History Review New Series Vol. 37 No. 4 (Nov. 1984) pp. 473–488.
