Year	% of land area
1961	6.82261208576998
1962	6.82261208576998
1963	6.82261208576998
1964	6.82261208576998
1965	6.82261208576998
1966	6.82261208576998
1967	6.82261208576998
1968	6.82261208576998
1969	6.82261208576998
1970	6.82261208576998
1971	6.82261208576998
1972	6.82261208576998
1973	6.82261208576998
1974	6.82261208576998
1975	6.82261208576998
1976	6.82261208576998
1977	6.82261208576998
1978	6.82261208576998
1979	6.82261208576998
1980	6.82261208576998
1981	7.212475633528265
1982	7.212475633528265
1983	5.847953216374268
1984	5.847953216374268
1985	5.847953216374268
1986	5.847953216374268
1987	5.847953216374268
1988	5.847953216374268
1989	5.847953216374268
1990	6.82261208576998
1991	6.82261208576998
1992	6.82261208576998
1993	6.82261208576998
1994	6.82261208576998
1995	5.847953216374268
1996	5.847953216374268
1997	5.847953216374268
1998	4.8732943469785575
1999	4.8732943469785575
2000	4.8732943469785575
2001	4.483430799220272
2002	4.483430799220272
2003	4.483430799220272
2004	4.28849902534113
2005	4.28849902534113
2006	4.28849902534113
2007	4.28849902534113
2008	4.28849902534113
2009	4.28849902534113
2010	4.28849902534113
2011	4.28849902534113
2012	4.28849902534113
2013	4.28849902534113
2014	4.28849902534113
2015	4.28849902534113
2016	4.28849902534113
2017	4.28849902534113
2018	4.28849902534113
2019	4.28849902534113
2020	4.28849902534113
2021	4.28849902534113