Year	Number of
1990	122.46
1991	122.71
1992	122.37
1993	120.92
1994	121.54
1995	116.99
1996	114.28
1997	112.3
1998	107.86
1999	104.65
2000	104.19
2001	102.43
2002	100.85
2003	102.08
2004	101.22
2005	100.58
2006	101.19
2007	100
2008	97.99
2009	96.71
2010	96.92
2011	97.09
2012	97.69
2013	101.2
2014	101.75
2015	105.13
2016	106.71