2024 | A | AA | AAA |
2023 | A | AA | AAA |
2022 | A | AA | AAA |
2021 | A | AA | AAA |
2020 | A | AA | AAA |
2019 | A | AA | AAA |
2018 | A | AA | AAA |
2017 | A | AA | AAA |
2016 | A | AA | AAA |
2015 | A | AA | AAA |
2014 | A | AA | AAA |
2013 | A | AA | AAA |
2012 | A | AA | AAA |
2011 | A | AA | AAA |
2110 | A | AA | AAA |
2009 | A | AA | AAA |
2008 | A | AA | AAA |
2007 | A | AA | AAA |
2006 | A | AA | AAA |
2005 | A | AA | AAA |
2004 | A | AA | AAA |
2003 | A | AA | AAA |
2002 | A | AA | AAA |
2001 | A | AA | AAA |
2000 | A | AA | AAA |
1999 | A | AA | AAA |
1998 | A | AA | AAA |
1997 | A | AA | AAA |
1996 | B | A | AA |
1995 | A | AA | |
1994 | A | AA | |
1993 | A | AA | |
1992 | A | AA | |
1991 | A | AA | |
1990 | A | AA | |
1989 | A | AA | |
1988 | A | AA | |
1987 | A | AA | |
1986 | A | AA | |
1985 | A | AA | |
1984 | A | AA | |
1983 | A | AA | |
1982 | A | AA | |
1981 | A | AA | |
1980 | A | AA | |
1979 | A | AA | |
1978 | A | AA | |
1977 | A | AA | |
1976 | A | AA | |
1975 | * | | |