Year	Number of
1990	149.82
1991	150.61
1992	151.73
1993	150.12
1994	151.14
1995	154.03
1996	164.75
1997	175.2
1998	179.95
1999	171.75
2000	161.46
2001	147.25
2002	138.88
2003	129.65
2004	123
2005	117.61
2006	115.05
2007	113.27
2008	111
2009	109.22
2010	108.63
2011	108.5
2012	109.36
2013	111.78
2014	114.59
2015	117.94
2016	121.65