Year	Number of
1990	318.3
1991	336.15
1992	358.95
1993	373.55
1994	394.57
1995	396.59
1996	383.57
1997	373.71
1998	375.3
1999	373.75
2000	383.07
2001	384.85
2002	389.06
2003	400.49
2004	424.17
2005	441.15
2006	467.11
2007	496.11
2008	517.04
2009	542.77
2010	566.69
2011	599.23
2012	624.23
2013	666.49
2014	694.14
2015	722.37
2016	753.28