Year	Number
2000	12.92668
2001	12.41336
2002	12.63722
2003	13.55945
2004	14.60397
2005	14.89535
2006	14.21284
2007	16.72371
2008	16.67785
2009	16.69766
2010	14.83565
2011	14.51218
2012	15.02376
2013	14.6138
2014	14.73339
2015	17.5542
2016	17.42662
2017	16.65888