Year	Number of
1990	191.85
1991	204.36
1992	198.98
1993	212.02
1994	219.74
1995	209.03
1996	196.34
1997	197.51
1998	209.05
1999	209.03
2000	214.21
2001	218.83
2002	217.75
2003	216.03
2004	214.77
2005	217.52
2006	219.49
2007	221
2008	217.45
2009	214.49
2010	203.43
2011	210.28
2012	212.47
2013	219.29
2014	218.33
2015	217.7
2016	218.48