Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            310       302       18.016607  18.481857  18.208387  0.163495   18.129231 
2008            310       302       18.375034  19.162794  18.782959  0.221943   18.766896 
2009            310       302       18.616714  19.044607  18.866583  0.10344    18.877464 
2010            310       302       15.073357  15.336893  15.176376  0.062539   15.161018 
2011            310       302       16.800964  17.530464  17.228473  0.212726   17.307839 
2012            310       302       17.055206  17.426517  17.203526  0.083557   17.192897 
2013            310       302       17.417572  17.835285  17.558841  0.123275   17.515518 
2014            310       302       15.292607  16.782143  16.156871  0.431535   16.281197 
2015            310       302       17.315393  17.796215  17.520913  0.127121   17.481572 
2016            310       302       17.23431   17.691311  17.439832  0.124506   17.4165   
2017            310       302       18.653929  18.993071  18.808134  0.084193   18.798553 
2018            310       302       17.020679  18.176107  17.636346  0.320824   17.722018 
2019            310       302       16.106108  16.371857  16.232879  0.056896   16.227696 
2020            310       302       16.320276  17.164345  16.728011  0.215709   16.731982 
2021            310       302       15.633654  17.729038  16.669344  0.654256   16.655539 
2022            310       302       13.701357  14.675428  14.093667  0.228858   14.044714 
2023            310       302       15.810286  16.236464  15.969263  0.098228   15.952928