Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            469       445       18.270903  18.937098  18.658518  0.163953   18.684032 
2008            469       445       17.621935  18.598742  18.219447  0.243105   18.249226 
2009            469       445       18.859613  19.772161  19.412027  0.223064   19.441935 
2010            469       445       15.164645  15.95142   15.619441  0.189063   15.641    
2011            469       445       17.434999  18.349548  18.000452  0.221856   18.033484 
2012            469       445       16.831324  17.911678  17.538385  0.260193   17.570354 
2013            469       445       17.906193  18.838741  18.491433  0.229922   18.520775 
2014            469       445       16.413485  17.621     17.181514  0.289534   17.201807 
2015            469       445       17.894646  18.616451  18.337761  0.179631   18.359354 
2016            469       445       15.354871  16.603001  16.071028  0.312253   16.060904 
2017            469       445       17.063517  18.321291  17.80938   0.289304   17.814064 
2018            469       445       14.742419  16.112646  15.532699  0.33315    15.540581 
2019            469       445       15.021548  16.049709  15.65509   0.253971   15.683871 
2020            469       445       16.514774  17.438999  17.094265  0.219175   17.127548 
2021            469       445       14.514129  16.09071   15.43873   0.378816   15.490387 
2022            469       445       17.358774  18.605904  18.040611  0.313146   18.077354 
2023            469       445       15.137548  16.397806  16.011132  0.289919   16.09