Y \ X
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
1850
1849
1848
1847
1846
1845
1844
1843
1842
1841
1840
1839
1838
1837
1836
1835
1834
1833
1832
1831
1830