Year	% of land area
1961	7.575757575757576
1962	7.575757575757576
1963	8.116883116883116
1964	8.116883116883116
1965	8.116883116883116
1966	8.116883116883116
1967	8.441558441558442
1968	8.658008658008658
1969	8.658008658008658
1970	8.658008658008658
1971	8.658008658008658
1972	8.658008658008658
1973	8.852813852813853
1974	7.683982683982683
1975	6.569264069264069
1976	6.547619047619048
1977	6.547619047619048
1978	6.547619047619048
1979	6.547619047619048
1980	6.525974025974025
1981	6.6558441558441555
1982	6.8181818181818175
1983	6.8181818181818175
1984	6.8181818181818175
1985	5.952380952380952
1986	5.952380952380952
1987	5.844155844155844
1988	5.735930735930736
1989	5.627705627705628
1990	5.51948051948052
1991	5.303030303030303
1992	5.194805194805195
1993	4.978354978354979
1994	4.545454545454546
1995	4.545454545454546
1996	4.653679653679654
1997	4.653679653679654
1998	4.653679653679654
1999	4.545454545454546
2000	4.545454545454546
2001	4.437229437229438
2002	4.220779220779221
2003	4.437229437229438
2004	4.545454545454546
2005	4.653679653679654
2006	4.437229437229438
2007	3.8419913419913416
2008	3.4415584415584415
2009	3.939393939393939
2010	3.2359307359307357
2011	3.2359307359307357
2012	3.0844155844155843
2013	2.9545454545454546
2014	2.922077922077922
2015	2.857142857142857
2016	2.8582251082251084
2017	2.7532467532467533
2018	2.845205627705628
2019	2.962402597402597
2020	2.8077922077922075
2021	2.791017316017316