Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            4230      4141      20.950434  21.594267  21.241795  0.114205   21.218166 
2008            4230      4141      21.618099  22.334999  21.990702  0.148924   21.980133 
2009            4230      4141      20.6502    21.358267  21.099744  0.149658   21.123034 
2010            4230      4141      20.517233  21.719166  21.347612  0.270901   21.430067 
2011            4230      4141      23.237413  24.108931  23.650117  0.200749   23.649897 
2012            4230      4141      22.891399  23.5982    23.36244   0.16167    23.397734 
2013            4230      4141      20.4541    21.047434  20.7985    0.141378   20.824833 
2014            4230      4141      20.0611    20.4186    20.237577  0.07694    20.232834 
2015            4230      4141      22.606333  23.4042    23.100104  0.210015   23.186434 
2016            4230      4141      21.078167  21.946466  21.47877   0.195892   21.505667 
2017            4230      4141      23.049934  23.405968  23.273395  0.081799   23.287933 
2018            4230      4141      20.511801  21.334534  20.9558    0.203106   21.005033 
2019            4230      4141      20.527666  21.023199  20.779736  0.1127     20.801399 
2020            4230      4141      22.244101  23.152201  22.696658  0.197525   22.7505   
2021            4230      4141      20.299601  21.2861    20.645126  0.249382   20.560534 
2022            4230      4141      21.536066  22.1416    21.839731  0.124989   21.841633 
2023            4230      4141      21.428139  22.261724  21.988768  0.210793   22.069828