Year	Number
1992	5.1516659894
1993	5.4262567481
1994	5.7009490915
1995	5.9755906426
1996	6.2502321936
1997	6.5248737447
1998	6.7995152958
1999	7.0741568468
2000	7.3487983979
2001	7.6221764889
2002	7.89555458
2003	8.1599741685
2004	8.4333459105
2005	8.7067176525
2006	8.9800893946
2007	8.982121089
2008	8.982121089
2009	8.982121089
2010	8.982121089
2011	8.982121089
2012	8.982121089
2013	8.982121089
2014	8.982121089
2015	8.982121089
2016	8.982121089
2017	8.982121089
2018	8.982121089
2019	8.982121089
2020	8.982121089