Year	Number
2006	0.881640553474426
2007	0.546154081821442
2008	0.53279185295105
2009	0.400019586086273
2010	0.303434699773788
2011	0.30920284986496
2012	0.316412746906281
2013	0.314557880163193
2014	0.278648048639297
2015	0.280024200677872
2016	0.268614619970322
2017	0.276849776506424
2018	0.272309929132462
2019	0.273571819067001
2020	0.290003538131714
2021	0.290525585412979
2022	0.269768208265305