Year	% of land area
1961	2.8230519838556716
1962	2.8230519838556716
1963	2.8230519838556716
1964	2.8142299464061225
1965	2.8054079089565738
1966	2.8054079089565738
1967	2.809818927681348
1968	2.8230519838556716
1969	2.8318740213052203
1970	2.8406960587547694
1971	2.853929114929093
1972	2.8671621711034163
1973	2.8759842085529654
1974	2.889217264727289
1975	2.8870117553649015
1976	2.9068613396263867
1977	2.9156833770759354
1978	2.92009439580071
1979	2.911272358351161
1980	2.92009439580071
1981	2.9333274519750336
1982	2.9289164332502593
1983	2.9333274519750336
1984	2.9421494894245828
1985	2.9553825455989062
1986	2.9642045830484554
1987	2.9553825455989062
1988	2.9553825455989062
1989	2.9553825455989062
1990	2.9421494894245828
1991	2.946560508149357
1992	2.9553825455989062
1993	2.9553825455989062
1994	2.9553825455989062
1995	2.9553825455989062
1996	2.9553825455989062
1997	2.9553825455989062
1998	2.9553825455989062
1999	2.9553825455989062
2000	2.9553825455989062
2001	2.9553825455989062
2002	2.9553825455989062
2003	2.9553825455989062
2004	2.9553825455989062
2005	2.9553825455989062
2006	2.9553825455989062
2007	2.9553825455989062
2008	2.977437639222779
2009	3.498820052491123
2010	4.020202465759467
2011	4.541584879027812
2012	5.062085088551201
2013	5.198385567146733
2014	5.431728457687303
2015	5.49612933106901
2016	5.585231909309455
2017	5.840629893473897
2018	5.952228667210693
2019	6.0342736154914975
2020	6.0342736154914975
2021	6.0342736154914975