
| 2024 | 2.32 | 4.13 | 40.9 | 56.1% |
| 2023 | 2.44 | 4.05 | 40.4 | 60.2% |
| 2022 | 2.33 | 3.77 | 37.84 | 61.7% |
| 2021 | 2.33 | 3.51 | 35.46 | 66.5% |
| 2020 | 2.21 | 3.58 | 36.55 | 61.7% |
| 2019 | 2.33 | 3.68 | 37.86 | 63.2% |
| 2018 | 2.31 | 3.19 | 33.12 | 72.5% |
| 2017 | 2.27 | 2.87 | 30.15 | 79% |
| 2016 | 2.29 | 2.77 | 29.51 | 82.5% |
| 2015 | 2.4 | 2.51 | 27.01 | 95.8% |
| 2014 | 2.3 | 2.2 | 24.02 | 104.6% |
| 2013 | 2.28 | 1.95 | 21.51 | 117.1% |
| 2012 | 2.34 | 1.98 | 22.15 | 117.9% |
| 2011 | 2.33 | 1.9 | 21.46 | 122.6% |
| 2010 | 2.25 | 1.72 | 19.62 | 130.9% |
| 2009 | 2.27 | 1.55 | 17.94 | 146.1% |
| 2008 | 2.07 | 1.45 | 17.07 | 142.5% |
| 2007 | 2.12 | 1.34 | 16.03 | 157.9% |
| 2006 | 2.09 | 1.23 | 14.98 | 170.2% |
| 2005 | 1.91 | 1.14 | 14.01 | 168% |
| 2004 | 1.7 | 1.1 | 13.66 | 154.6% |
| 2003 | 1.43 | 0.84 | 10.58 | 170.1% |
| 2002 | 1.31 | 0.76 | 9.66 | 171.7% |
| 2001 | 1.2 | 0.64 | 8.23 | 186.7% |
| 2000 | 1.11 | 0.57 | 7.37 | 195.7% |
| 1999 | 1.01 | 0.52 | 6.86 | 192.1% |
| 1998 | 0.92 | 0.48 | 6.34 | 192.6% |
| 1997 | 0.79 | 0.44 | 5.95 | 179.4% |
| 1996 | 0.72 | 0.43 | 5.82 | 168.1% |
| 1995 | 0.62 | 0.36 | 4.94 | 173.6% |
| 1994 | 0.51 | 0.29 | 4.07 | 178.4% |
| 1993 | 0.46 | 0.26 | 3.74 | 177% |
| 1992 | 0.42 | 0.22 | 3.22 | 191.6% |
| 1991 | 0.33 | 0.2 | 2.99 | 164.9% |
| 1990 | 0.26 | 0.18 | 2.81 | 138.8% |
| 1989 | 0.22 | 0.17 | 2.63 | 127.3% |
| 1988 | 0.19 | 0.16 | 2.57 | 116.6% |
| 1987 | 0.18 | 0.15 | 2.47 | 121.4% |
| 1986 | 0.17 | 0.14 | 2.26 | 123% |
| 1985 | 0.15 | 0.13 | 2.19 | 119% |
| 1984 | 0.14 | 0.12 | 2.1 | 114.5% |
| 1983 | 0.17 | 0.14 | 2.41 | 127.5% |
| 1982 | 0.17 | 0.13 | 2.42 | 129.4% |
| 1981 | 0.16 | 0.13 | 2.38 | 127.3% |
| 1980 | 0.14 | 0.11 | 2.17 | 123.7% |