| 年度 | 实际值 |
|---|---|
| 1993 | 30.4 |
| 1994 | |
| 1995 | 32.6 |
| 1996 | 32.9 |
| 1997 | 33.9 |
| 1998 | 33.9 |
| 1999 | 34.7 |
| 2000 | 35.5 |
| 2001 | 1.97333333333333 |
| 2002 | |
| 2003 | 36.17 |
| 2004 | 37.51 |
| 2005 | 40 |
| 2006 | 41.1 |
| 2007 | 42.2 |
| 2008 | 43 |
| 2009 | |
| 2010 | 43.08 |
| 2011 | 42.6 |
| 2012 | 42.67 |
| 2013 | 42.79 |
| 2014 | 42.85 |
| 2015 | 43.04 |
| 2016 | 42.98 |
| 2017 | 43 |
| 2018 | 43 |