Year	% of land area
1961	8.695652173913043
1962	8.695652173913043
1963	8.695652173913043
1964	8.695652173913043
1965	8.695652173913043
1966	8.695652173913043
1967	8.695652173913043
1968	8.695652173913043
1969	8.695652173913043
1970	8.695652173913043
1971	8.695652173913043
1972	8.695652173913043
1973	8.695652173913043
1974	8.695652173913043
1975	8.695652173913043
1976	8.695652173913043
1977	8.695652173913043
1978	8.695652173913043
1979	8.695652173913043
1980	8.695652173913043
1981	8.695652173913043
1982	10.869565217391305
1983	10.869565217391305
1984	10.869565217391305
1985	10.869565217391305
1986	10.869565217391305
1987	10.869565217391305
1988	8.695652173913043
1989	8.695652173913043
1990	6.521739130434782
1991	6.521739130434782
1992	6.521739130434782
1993	6.521739130434782
1994	6.521739130434782
1995	6.521739130434782
1996	6.521739130434782
1997	6.521739130434782
1998	6.521739130434782
1999	6.521739130434782
2000	6.521739130434782
2001	6.521739130434782
2002	6.521739130434782
2003	6.521739130434782
2004	6.521739130434782
2005	6.521739130434782
2006	6.521739130434782
2007	4.3478260869565215
2008	4.3478260869565215
2009	4.130434782608695
2010	3.260869565217391
2011	2.88695652173913
2012	2.9565217391304346
2013	3.0434782608695654
2014	3.0434782608695654
2015	3.0434782608695654
2016	3.0434782608695654
2017	3.0434782608695654
2018	3.0434782608695654
2019	3.0434782608695654
2020	3.0434782608695654
2021	3.0434782608695654