Year	Number of
1990	16932.86
1991	16942.79
1992	17648.35
1993	19756.72
1994	20915.63
1995	20022.66
1996	18947.3
1997	18267.95
1998	18299.09
1999	19557.66
2000	20216.93
2001	20639.94
2002	21179.54
2003	21598.04
2004	21509.77
2005	21885.21
2006	21208.43
2007	21192.54
2008	21769.81
2009	21332.41
2010	21565.07
2011	21318.82
2012	21106.72
2013	21121.92
2014	21340.18
2015	21705.95
2016	22466.88