Year	% of land area
1961	3.8190364277320796
1962	3.916960438699569
1963	3.916960438699569
1964	3.916960438699569
1965	3.916960438699569
1966	3.916960438699569
1967	3.936545240893067
1968	3.936545240893067
1969	4.014884449667059
1970	4.073638856247552
1971	4.151978065021543
1972	4.151978065021543
1973	4.054054054054054
1974	4.054054054054054
1975	4.093223658441049
1976	4.151978065021543
1977	4.191147669408539
1978	4.2499020759890325
1979	4.308656482569527
1980	4.36741088915002
1981	4.426165295730513
1982	4.484919702311007
1983	4.5436741088915005
1984	4.602428515471994
1985	4.661182922052487
1986	4.719937328632981
1987	4.719937328632981
1988	4.759106933019976
1989	4.896200548374462
1990	4.896200548374462
1991	4.99412455934195
1992	5.09204857030944
1993	5.287896592244419
1994	5.679592636114375
1995	5.679592636114375
1996	5.581668625146886
1997	5.483744614179397
1998	5.483744614179397
1999	5.483744614179397
2000	5.483744614179397
2001	5.483744614179397
2002	5.679592636114375
2003	5.679592636114375
2004	5.679592636114375
2005	5.483744614179397
2006	5.777516647081864
2007	5.875440658049354
2008	5.875440658049354
2009	6.071288679984333
2010	6.169212690951821
2011	6.169212690951821
2012	6.169212690951821
2013	6.2475518997258135
2014	6.2475518997258135
2015	6.2475518997258135
2016	6.335683509596553
2017	6.423815119467294
2018	6.462984723854288
2019	6.521739130434782
2020	6.717587152369761
2021	7.207207207207207