Year	Number of
1990	80.35
1991	81.52
1992	83.02
1993	85.58
1994	88.54
1995	88.38
1996	86.53
1997	84.96
1998	84.71
1999	84.94
2000	85.26
2001	88.52
2002	87.07
2003	90.2
2004	90.7
2005	95.14
2006	94.87
2007	97.92
2008	101.12
2009	103
2010	102.8
2011	106.21
2012	108.95
2013	112.92
2014	115.43
2015	118.43
2016	120.81