Year	days
2009	70.6
2010	69.85
2011	69.85
2012	69.55
2013	69.30727272727273
2014	68.89818181818181
2015	68.64863636363637
2016	68.04227272727273
2017	67.90590909090909
2018	67.17863636363637
2019	66.67863636363637