Year	number
2005	40.296
2006	40.07086614173228
2007	39.63779527559055
2008	38.30708661417323
2009	38.015625
2010	37.265625
2011	35.5968992248062
2012	33.29545454545455
2013	32.50156028368794
2014	31.430638297872335
2015	30.74978723404255
2016	29.40936170212766
2017	28.08191489361702
2018	27.9968085106383
2019	27.31595744680851
