| 年度 | 实际值 |
|---|---|
| 1995 | 32.1 |
| 1996 | 32.1 |
| 1997 | 39.22 |
| 1998 | 35.7 |
| 1999 | 38.5 |
| 2000 | 39.8 |
| 2001 | 39.77 |
| 2002 | 39.74 |
| 2003 | 41.61 |
| 2004 | 42.33 |
| 2005 | 44.01 |
| 2006 | 44.84 |
| 2007 | 44.39 |
| 2008 | 44.52 |
| 2009 | |
| 2010 | 42.23 |
| 2011 | 41.49 |
| 2012 | 41.64 |
| 2013 | 44.29 |
| 2014 | 47.15 |
| 2015 | 48.89 |
| 2016 | 50.83 |
| 2017 | |
| 2018 | 55.36 |