Year	Number
1996	5.31914901733398
1998	4.78723382949829
2000	10.0529098510742
2002	6.87830686569214
2003	5.52763795852661
2004	10.6796112060547
2005	20.3883495330811
2006	15.9420289993286
2007	14.0096616744995
2008	14.9038457870483
2009	13.2701425552368
2010	11.8483409881592
2011	10.4265403747559
2012	9.47867298126221
2013	12.7962083816528
2014	9.5238094329834
2015	11.9047622680664
2016	12.380952835083
2017	15.7142858505249
2018	17.9245281219482
2019	13.2075471878052
2020	17.9245281219482
2021	15.5660381317139
2022	19.3396224975586