| 1971 | 0.092 |
| 1972 | 1 |
| 1973 | |
| 1974 | 0.5 |
| 1975 | |
| 1976 | |
| 1977 | 0.5 |
| 1978 | |
| 1979 | 1 |
| 1980 | |
| 1981 | |
| 1982 | 1.8 |
| 1983 | |
| 1984 | 4 |
| 1985 | 11.4 |
| 1986 | 4 |
| 1987 | 11 |
| 1988 | |
| 1989 | |
| 1990 | 44 |
| 1991 | |
| 1992 | 300 |
| 1993 | |
| 1994 | 35 |
| 1995 | |
| 1996 | 35.9 |
| 1997 | 525 |
| 1998 | 400 |
| 1999 | 80 |
| 2000 | 3561 |
| 2001 | |
| 2002 | 5935 |
| 2003 | 9726 |
| 2004 | |
| 2005 | 25150 |
| 2006 | 27100 |
| 2007 | |
| 2008 | 76383 |
| 2009 | |
| 2010 | 152766 |
| 2011 | |
| 2012 | 305532 |
| 2013 | |
| 2014 | 611064 |
| 2015 | |
| 2016 | 1222128 |
| 2017 | |
| 2018 | 2444256 |
| 2019 | |
| 2020 | 4888512 |
| 2021 | |
| 2022 | 9800000 |
| 2023 | |
| 2024 | 19554048 |
| 2025 | |
| 2026 | 39108096 |
| 2027 | |
| 2028 | 78216192 |
| 2029 | |
| 2030 | 1.56E+08 |