Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            4230      4141      18.101194  19.404968  18.924958  0.302856   19.009613 
2008            4230      4141      16.887161  18.59329   17.662743  0.292211   17.674517 
2009            4230      4141      18.981936  19.688032  19.391733  0.145161   19.400227 
2010            4230      4141      15.402678  16.406033  15.907778  0.202822   15.939968 
2011            4230      4141      19.357355  20.276323  19.772362  0.157539   19.753935 
2012            4230      4141      20.231001  21.172516  20.760457  0.18604    20.795355 
2013            4230      4141      15.972226  17.578773  16.66416   0.25262    16.665806 
2014            4230      4141      15.624129  17.243904  16.312811  0.28996    16.324806 
2015            4230      4141      17.010872  19.869226  18.393085  0.609696   18.524452 
2016            4230      4141      18.48942   19.173225  18.863471  0.172812   18.890516 
2017            4230      4141      19.218452  19.968452  19.514162  0.148785   19.48287  
2018            4230      4141      18.594     19.730742  19.05292   0.268495   18.966549 
2019            4230      4141      16.470903  18.058903  17.221691  0.343217   17.194548 
2020            4230      4141      20.262968  20.86087   20.533172  0.145095   20.508226 
2021            4230      4141      17.78129   18.842064  18.246791  0.227276   18.239807 
2022            4230      4141      17.632999  18.774612  18.117897  0.21893    18.056419 
2023            4230      4141      20.233677  20.961935  20.528343  0.171425   20.530193