Year	Number
1996	2.0198985103714246
1997	2.1553399765653016
1998	2.4190315269411307
1999	3.362265069561761
2000	2.9224717022867885
2001	5.836859532685011
2002	4.965244589710711
2003	4.9322165051838125
2004	3.9956273075437245
2005	4.741092237799704
2006	5.765410457211765
2007	4.685730193235471
2008	3.5138882199646257
2009	5.1054615482721
2010	4.71960498360332
2011	4.356775472004943
2012	5.0124553461938435
2013	4.612117472677588
2014	4.558856797111972
2015	4.2227916835352115
2016	4.312080704331636
2017	3.982004583257778
2018	3.966161637285312
2019	4.228661139138902
2020	5.264779815265823
2021	4.080064349324816
2022	3.5917493426493032
2023	4.369101180216331