| 年度 | 实际值 |
|---|---|
| 1995 | 28.9 |
| 1996 | 31.7 |
| 1997 | 33.52 |
| 1998 | 35.1 |
| 1999 | 35.2 |
| 2000 | 35.8 |
| 2001 | 37.59 |
| 2002 | 37.71 |
| 2003 | 37.69 |
| 2004 | 37.27 |
| 2005 | 39.83 |
| 2006 | 40.06 |
| 2007 | 40.31 |
| 2008 | 40.36 |
| 2009 | |
| 2010 | 40.15 |
| 2011 | 40.51 |
| 2012 | 42.49 |
| 2013 | 43.64 |
| 2014 | 44.07 |
| 2015 | 45.24 |
| 2016 | 45.23 |
| 2017 | |
| 2018 | 45.9 |