Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            2271      1991      13.919912  14.486496  14.323688  0.085132   14.320121 
2008            2271      1991      13.587205  14.099582  13.971508  0.073551   13.981016 
2009            2271      1991      13.430567  13.995896  13.842933  0.073962   13.849619 
2010            2271      1991      13.873192  14.573449  14.139479  0.173105   14.086924 
2011            2271      1991      14.059154  14.488689  14.324227  0.078395   14.316564 
2012            2271      1991      15.30232   15.654063  15.467728  0.071042   15.466391 
2013            2271      1991      13.779321  14.517485  14.073609  0.193372   14.040917 
2014            2271      1991      13.348712  13.678754  13.493426  0.071539   13.495288 
2015            2271      1991      13.905449  14.469844  14.121445  0.140197   14.104142 
2016            2271      1991      14.798532  15.425377  15.081756  0.1476     15.063688 
2017            2271      1991      14.503436  15.138535  14.841958  0.138544   14.864739 
2018            2271      1991      13.580641  14.287583  14.088704  0.119721   14.110863 
2019            2271      1991      14.070975  14.736038  14.552746  0.098675   14.567258 
2020            2271      1991      14.833566  15.58294   15.185016  0.182856   15.170331 
2021            2271      1991      14.636421  15.60503   15.12563   0.241801   15.121289 
2022            2271      1991      13.926758  14.390206  14.2215    0.11558    14.260129 
2023            2271      1991      14.927463  15.69219   15.282699  0.191566   15.278967