Year	Number
1996	5.85106372833252
1998	4.25531911849976
2000	10.582010269165
2002	13.7566137313843
2003	15.0753765106201
2004	18.9320392608643
2005	21.3592224121094
2006	23.1884059906006
2007	20.2898559570313
2008	21.634614944458
2009	16.5876770019531
2010	18.4834117889404
2011	23.6966819763184
2012	31.7535552978516
2013	27.488151550293
2014	35.238094329834
2015	35.7142868041992
2016	40.476188659668
2017	34.761905670166
2018	37.7358474731445
2019	27.8301887512207
2020	24.056604385376
2021	27.3584899902344
2022	29.7169818878174