Year | lnR | Year | lnR | Year | lnR |
1953 | 7.232 | 1973 | 11.170 | 1993 | 9.403 |
1954 | 6.872 | 1974 | 9.278 | 1994 | 9.383 |
1955 | 6.691 | 1975 | 10.145 | 1995 | 8.897 |
1956 | 6.545 | 1976 | 10.931 | 1996 | 9.506 |
1957 | 6.736 | 1977 | 11.432 | 1997 | 8.958 |
1958 | 8.229 | 1978 | 11.453 | 1998 | 8.906 |
1959 | 8.548 | 1979 | 10.644 | 1999 | 7.844 |
1960 | 6.807 | 1980 | 12.588 | 2000 | 8.477 |
1961 | 6.412 | 1981 | 12.195 | 2001 | 8.414* |
1962 | 6.103 | 1982 | 11.959 | 2002 | 7.687* |
1963 | 5.652 | 1983 | 12.102 | 2003 | 7.592* |
1964 | 5.153 | 1984 | 12.268 | 2004 | 7.352* |
1965 | 4.963 | 1985 | 12.421 | 2005 | 8.338* |
1966 | 5.136 | 1986 | 12.468 | 2006 | 7.903* |
1967 | 5.380 | 1987 | 11.961 | 2007 | 7.994* |
1968 | 5.649 | 1988 | 10.037 | 2008 | 8.501* |
1969 | 6.180 | 1989 | 9.875 | 2009 | 8.149* |
1970 | 7.363 | 1990 | 8.843 | 2010 | 9.919* |
1971 | 9.133 | 1991 | 8.577 | 2011 | 9.125* |
1972 | 7.462 | 1992 | 10.216 | 2012 | 9.776* |