Year	hours
2005	343.27777777777777
2006	347.84065934065933
2007	343.95604395604397
2008	317.7467032967033
2009	301.18967391304346
2010	294.1771739130435
2011	289.19565217391306
2012	285.45212765957444
2013	310.2725
2014	304.2921078431372
2015	301.8631862745098
2016	282.4587745098039
2017	276.1818137254902
2018	272.5244607843137
2019	265.86024509803923