Year	Number
1996	11.81818
1999	8.75
2000	10.55556
2001	12.4
2002	15.16667
2003	17.76471
2004	12.32609
2005	17.66667
2006	17.52727
2007	18.1157
2009	20.12102
2010	20.5414
2011	19.20408