Year	number
2005	14.208333333333334
2006	14.12
2007	14.2
2008	14.038461538461538
2009	13.923076923076923
2010	14
2011	14
2012	14
2013	13.88888888888889
2014	13.962962962962964
2015	14.037037037037036
2016	13.88888888888889
2017	13.88888888888889
2018	13.851851851851851
2019	13.851851851851851