Year	Number of
1990	83.54
1991	84.73
1992	86.82
1993	88.42
1994	90.16
1995	92.08
1996	93.32
1997	95.42
1998	98.16
1999	98.04
2000	98.52
2001	97.85
2002	97.8
2003	99.63
2004	101.74
2005	103.83
2006	106.86
2007	109.38
2008	111.86
2009	114.81
2010	120.72
2011	124.51
2012	129.73
2013	134.66
2014	138.98
2015	143.34
2016	148.31