Year	% of land area
1961	90.91345342573827
1962	90.91345342573827
1963	90.91345342573827
1964	90.9121609674679
1965	90.91345342573827
1966	90.91345342573827
1967	90.91345342573827
1968	90.91345342573827
1969	90.89342032254741
1970	90.91409965487345
1971	90.91345342573827
1972	90.91345342573827
1973	90.91345342573827
1974	90.91345342573827
1975	90.91345342573827
1976	81.1353603811995
1977	81.40871530538429
1978	81.37123401554335
1979	80.59317413677627
1980	80.51174926574251
1981	80.46780568454969
1982	80.47168305936081
1983	80.76313239933087
1984	80.52467384844628
1985	80.51174926574251
1986	80.47556043417194
1987	80.70691046456948
1988	80.92985951620953
1989	81.12243579849574
1990	81.20256821125913
1991	81.50888082133852
1992	79.86745881795947
1993	76.98139950020717
1994	76.55811941665863
1995	76.55811941665863
1996	76.55811941665863
1997	83.29311946359425
1998	83.44886068517471
1999	84.1920241906416
2000	84.31351526805706
2001	84.09347424752535
2002	84.08603033189222
2003	73.50127018377107
2004	73.43635319426707
2005	73.29166784423127
2006	73.66312252799567
2007	73.63275254896212
2008	73.5213912374525
2009	73.36925476239907
2010	73.33884675729539
2011	73.32647759405884
2012	73.2494851542796
2013	73.22527304109256
2014	73.00162900127899
2015	72.99021727585597
2016	72.92367713093176
2017	72.86357138334535
2018	72.84163479969563
2019	72.8032862891056
2020	72.35894359043772
2021	72.31505219559206