| 年度 | 实际值 |
|---|---|
| 1992 | 36.62 |
| 1993 | 37.17 |
| 1994 | 37.75 |
| 1995 | 38.42 |
| 1996 | 38.93 |
| 1997 | 39.6 |
| 1998 | 40.31 |
| 1999 | 40.08 |
| 2000 | 40.5 |
| 2001 | 41.09 |
| 2002 | 41.76 |
| 2003 | 42.15 |
| 2004 | 43.18 |
| 2005 | 43.97 |
| 2006 | 44.69 |
| 2007 | 44.97 |
| 2008 | 45.57 |
| 2009 | |
| 2010 | 45.79 |
| 2011 | 46.3 |
| 2012 | 46.3 |
| 2013 | 46.8 |
| 2014 | 47.8 |
| 2015 | 45.95 |
| 2016 | 47 |
| 2017 | 47 |
| 2018 | 48 |