Year	% of land area
1961	51.04782375067168
1962	51.04782375067168
1963	51.04782375067168
1964	51.04782375067168
1965	51.04782375067168
1966	51.04782375067168
1967	51.04782375067168
1968	51.04782375067168
1969	51.04782375067168
1970	51.04782375067168
1971	51.04782375067168
1972	51.04782375067168
1973	51.04782375067168
1974	51.04782375067168
1975	51.04782375067168
1976	51.04782375067168
1977	51.04782375067168
1978	53.73455131649651
1979	53.73455131649651
1980	53.73455131649651
1981	53.73455131649651
1982	53.73455131649651
1983	53.73455131649651
1984	59.108006448146156
1985	59.108006448146156
1986	59.108006448146156
1987	60.72004298764105
1988	61.25738850080602
1989	61.25738850080602
1990	61.25738850080602
1991	61.79473401397099
1992	61.79473401397099
1993	63.406770553465876
1994	64.4814615797958
1995	65.55615260612574
1996	66.63084363245567
1997	67.70553465878561
1998	67.70553465878561
1999	68.24288017195056
2000	68.78022568511552
2001	69.85491671144545
2002	70.39226222461042
2003	70.92960773777538
2004	71.46695325094036
2005	71.46695325094036
2006	71.46695325094036
2007	71.46695325094036
2008	71.46695325094036
2009	71.46695325094036
2010	71.46695325094036
2011	71.46695325094036
2012	71.46695325094036
2013	71.46695325094036
2014	71.46695325094036
2015	71.46695325094036
2016	71.46695325094036
2017	71.46695325094036
2018	71.46695325094036
2019	71.46695325094036
2020	71.46695325094036
2021	71.46695325094036