Year	Number
1996	25.5319156646729
1998	27.659574508667
2000	30.1587295532227
2002	40.7407417297363
2003	32.6633148193359
2004	45.6310691833496
2005	30.5825233459473
2006	31.4009666442871
2007	25.1207733154297
2008	27.884614944458
2009	23.6966819763184
2010	24.6445503234863
2011	20.3791465759277
2012	28.4360198974609
2013	34.1232223510742
2014	44.761905670166
2015	31.9047622680664
2016	30.9523811340332
2017	32.3809509277344
2018	31.6037731170654
2019	29.2452831268311
2020	30.6603775024414
2021	30.6603775024414
2022	29.7169818878174