Year	Number
1995	29.51903
1996	29.07781
1997	29.29296
1998	28.78831
1999	28.82644
2000	29.41538
2001	29.60712
2002	30.14709
2003	30.03624
2004	30.20714
2005	30.53681
2006	30.78041
2007	29.06635
2008	30.52544
2009	30.34969
2010	29.26776
2011	29.45145
2012	30.64478
2013	30.4416
2014	29.84015
2015	30.38739
2016	30.34188
2017	33.04587
2018	30.39888