Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            595       550       16.869167  18.881399  18.151779  0.571081   18.3579   
2008            595       550       16.485901  18.678934  17.909674  0.681213   18.25985  
2009            595       550       16.712767  18.084433  17.605284  0.374662   17.746616 
2010            595       550       16.8883    18.5849    18.042729  0.5584     18.275634 
2011            595       550       16.974518  18.813345  18.236783  0.569999   18.568414 
2012            595       550       17.850533  18.7199    18.3851    0.183753   18.435217 
2013            595       550       14.060166  17.309866  16.01602   1.010973   16.444217 
2014            595       550       14.71      17.929132  16.674987  1.002867   17.117216 
2015            595       550       16.415167  19.189301  18.153455  0.695282   18.41235  
2016            595       550       16.025766  17.757334  17.003493  0.444719   17.1543   
2017            595       550       17.766533  20.144934  18.995438  0.630749   19.1454   
2018            595       550       13.9103    16.714333  15.739415  0.798006   16.120266 
2019            595       550       16.557766  18.792334  18.062252  0.644222   18.403333 
2020            595       550       16.572666  17.797434  17.257624  0.337163   17.34505  
2021            595       550       17.169567  18.072901  17.689991  0.283209   17.810067 
2022            595       550       17.208733  18.850267  18.114216  0.471732   18.236067 
2023            595       550       17.386414  18.957483  18.45224   0.421074   18.645914