Year	Number of
1990	2284.92
1991	2228.77
1992	2185.46
1993	2223.38
1994	2251.91
1995	2265.21
1996	2230.71
1997	2175.45
1998	2139.04
1999	2092.35
2000	2058.62
2001	2034.29
2002	1983.53
2003	1971.48
2004	1974.03
2005	1963.15
2006	1943.14
2007	1915.36
2008	1886.87
2009	1908.49
2010	1905.7
2011	1896.31
2012	1911.89
2013	1907.74
2014	1889.71
2015	1905.69
2016	1927.8