Year	Number of
1990	116.13
1991	123.91
1992	128.67
1993	129.09
1994	139.36
1995	137.6
1996	134.61
1997	128.46
1998	125.38
1999	125.66
2000	127.32
2001	127.7
2002	131.35
2003	136.9
2004	143.93
2005	157.53
2006	162.73
2007	169.85
2008	175.92
2009	186.99
2010	199.54
2011	194.23
2012	203.94
2013	202.18
2014	209.98
2015	215.35
2016	214.14