Year	Number of
1989	0.8031
1991	0.9261
1995	0.5725
1996	0.6701
1998	1.025
1999	0.814
2000	0.8146
2001	0.8619
2002	0.882
2003	0.8079
2004	0.4852
2005	0.4318
2006	0.2603
2007	0.1745
2008	0.2965
2009	0.2622
2010	0.3215
2011	0.1764
2012	0.1593