Annual % of land area
1961 11.72899130674762
1962 11.805651380647932
1963 11.882311454548242
1964 11.958971528448552
1965 11.958971528448552
1966 12.01263358017877
1967 12.026432393480828
1968 12.026432393480828
1969 12.050963617128927
1970 12.06629563190899
1971 12.112291676249177
1972 12.127623691029237
1973 12.127623691029237
1974 12.127623691029237
1975 12.127623691029237
1976 12.127623691029237
1977 12.127623691029237
1978 12.127623691029237
1979 12.127623691029237
1980 12.127623691029237
1981 12.127623691029237
1982 12.127623691029237
1983 12.127623691029237
1984 12.127623691029237
1985 12.127623691029237
1986 12.127623691029237
1987 12.127623691029237
1988 12.127623691029237
1989 12.127623691029237
1990 12.127623691029237
1991 12.127623691029237
1992 12.127623691029237
1993 11.995768363920703
1994 11.81025098508195
1995 11.733590911181638
1996 11.724391702313602
1997 11.782653358477837
1998 11.893043864894286
1999 11.733590911181638
2000 11.779586955521825
2001 11.779586955521825
2002 11.771920948131793
2003 11.91604188706438
2004 11.983502752096653
2005 11.966637535838585
2006 11.949772319580516
2007 11.949772319580516
2008 11.949772319580516
2009 11.94823911810251
2010 11.94823911810251
2011 11.945172715146498
2012 11.943639513668492
2013 11.93597350627846
2014 11.914508685586373
2015 11.905309476718335
2016 11.850114223510111
2017 11.804118179169924
2018 11.949772319580516
2019 11.940573110712478
2020 12.003434371310734
2021 12.003434371310734