Year	Number of
1990	127.31
1991	127.83
1992	121.36
1993	116.08
1994	114.63
1995	114.98
1996	121.32
1997	126.37
1998	131.83
1999	132.51
2000	127.69
2001	119.12
2002	111.1
2003	104.28
2004	98
2005	92.79
2006	90.4
2007	88.39
2008	87.98
2009	88.38
2010	89.93
2011	90.66
2012	91.44
2013	94.46
2014	97.3
2015	100.49
2016	103.64