
| 2024 | 0.44 | 2.28 | 194.5 | 19.4% |
| 2023 | 0.46 | 2.26 | 193.1 | 20.5% |
| 2022 | 0.57 | 2.41 | 207.2 | 23.5% |
| 2021 | 0.63 | 2.62 | 226.2 | 24% |
| 2020 | 0.47 | 2.35 | 203.8 | 20.2% |
| 2019 | 0.55 | 2.61 | 227.6 | 21.1% |
| 2018 | 0.4 | 2.62 | 229 | 15.2% |
| 2017 | 0.53 | 2.6 | 228.8 | 20.4% |
| 2016 | 0.54 | 2.6 | 229 | 20.6% |
| 2015 | 0.37 | 2.44 | 216.7 | 15% |
| 2014 | 0.44 | 2.42 | 215.6 | 18% |
| 2013 | 0.52 | 2.6 | 232.8 | 20% |
| 2012 | 0.5 | 2.53 | 227.8 | 19.6% |
| 2011 | 0.57 | 2.61 | 236.9 | 21.7% |
| 2010 | 0.56 | 2.81 | 256.7 | 19.8% |
| 2009 | 0.54 | 2.61 | 241.5 | 20.5% |
| 2008 | 0.5 | 2.86 | 267.4 | 17.3% |
| 2007 | 0.51 | 2.78 | 261.5 | 18.5% |
| 2006 | 0.49 | 2.77 | 262.3 | 17.8% |
| 2005 | 0.49 | 2.78 | 264.9 | 17.8% |
| 2004 | 0.49 | 2.8 | 269 | 17.4% |
| 2003 | 0.48 | 2.77 | 266.7 | 17.5% |
| 2002 | 0.48 | 2.68 | 259.4 | 18.1% |
| 2001 | 0.47 | 2.69 | 261.9 | 17.6% |
| 2000 | 0.49 | 2.7 | 263.3 | 18.1% |
| 1999 | 0.5 | 2.64 | 258.1 | 18.8% |
| 1998 | 0.47 | 2.66 | 260.4 | 17.5% |
| 1997 | 0.48 | 2.59 | 254.8 | 18.4% |
| 1996 | 0.44 | 2.58 | 254.3 | 17% |
| 1995 | 0.42 | 2.44 | 240.8 | 17.2% |
| 1994 | 0.41 | 2.4 | 237.7 | 17.1% |
| 1993 | 0.42 | 2.26 | 224.2 | 18.7% |
| 1992 | 0.44 | 2.29 | 228.3 | 19.4% |
| 1991 | 0.45 | 2.29 | 229.1 | 19.6% |
| 1990 | 0.46 | 2.21 | 222.1 | 20.6% |
| 1989 | 0.46 | 2.16 | 217.2 | 21.4% |
| 1988 | 0.5 | 2.14 | 216.3 | 23.1% |
| 1987 | 0.54 | 2.09 | 211 | 25.6% |
| 1986 | 0.54 | 2.03 | 204.8 | 26.8% |
| 1985 | 0.51 | 1.95 | 197 | 26.2% |
| 1984 | 0.45 | 1.87 | 189.7 | 23.9% |
| 1983 | 0.4 | 1.83 | 185.7 | 22.1% |
| 1982 | 0.33 | 1.86 | 189 | 17.9% |
| 1981 | 0.3 | 1.99 | 202.3 | 14.9% |
| 1980 | 0.3 | 2.12 | 215.6 | 14.1% |