| Year |
Total |
Public |
Private |
| Actual |
| 1996 |
16.9 |
17.1 |
15.5 |
| 1997 |
16.6 |
16.8 |
15.2 |
| 1998 |
16.3 |
16.4 |
15.0 |
| 1999 |
15.9 |
16.1 |
14.7 |
| 2000 |
15.9 |
16.0 |
14.5 |
| 2001 |
15.7 |
15.9 |
14.3 |
| 2002 |
15.7 |
15.9 |
14.1 |
| 2003 |
15.7 |
15.9 |
13.8 |
| 2004 |
15.5 |
15.8 |
13.7 |
| 2005 |
15.4 |
15.6 |
13.5 |
| 2006 |
15.3 |
15.6 |
13.2 |
| 2007 |
15.2 |
15.5 |
13.0 |
| 2008 |
15.0 |
15.3 |
12.8 |
| 2009 |
15.0 |
15.4 |
12.5 |
| 2010 |
15.0 |
15.2 |
12.4 |
| Projected |
|
|
|
| 2011 |
14.9 |
15.2 |
12.3 |
| 2012 |
14.8 |
15.2 |
12.3 |
| 2013 |
14.8 |
15.1 |
12.3 |
| 2014 |
14.7 |
15.0 |
12.2 |
| 2015 |
14.6 |
14.9 |
12.1 |
| 2016 |
14.5 |
14.8 |
12.1 |
| 2017 |
14.4 |
14.7 |
12.0 |
| 2018 |
14.3 |
14.6 |
11.9 |
| 2019 |
14.2 |
14.5 |
11.8 |
| 2020 |
14.1 |
14.4 |
11.7 |
| 2021 |
14.1 |
14.4 |
11.7 |