Year	Number
1996	3.19148945808411
1998	5.85106372833252
2000	7.40740728378296
2002	19.5767192840576
2003	18.0904521942139
2004	12.1359224319458
2005	10.6796112060547
2006	11.1111106872559
2007	22.2222213745117
2008	18.269229888916
2009	16.1137447357178
2010	15.6398105621338
2011	16.5876770019531
2012	12.3222751617432
2013	13.2701425552368
2014	23.3333339691162
2015	18.5714282989502
2016	20
2017	22.8571434020996
2018	19.8113212585449
2019	26.4150943756104
2020	26.8867931365967
2021	23.5849056243896
2022	21.2264156341553