Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            4230      4141      27.736     28.611767  28.331905  0.173482   28.355934 
2008            4230      4141      28.4464    29.666599  29.358763  0.291568   29.456533 
2009            4230      4141      28.387066  29.2815    28.729672  0.235006   28.666834 
2010            4230      4141      29.538567  30.537834  30.124696  0.223145   30.174967 
2011            4230      4141      28.978899  30.149366  29.683454  0.293306   29.698601 
2012            4230      4141      27.998632  28.759399  28.38118   0.190059   28.395733 
2013            4230      4141      28.651934  29.516768  29.146219  0.186199   29.196867 
2014            4230      4141      27.914801  28.747766  28.473985  0.177536   28.511833 
2015            4230      4141      28.848267  29.831934  29.538133  0.240258   29.618433 
2016            4230      4141      28.532499  29.415733  29.104992  0.189953   29.159166 
2017            4230      4141      27.239233  27.9816    27.797829  0.168566   27.8615   
2018            4230      4141      29.2194    29.9608    29.654906  0.186998   29.669132 
2019            4230      4141      28.143034  29.381433  28.969336  0.244899   29.042334 
2020            4230      4141      27.816433  28.830799  28.418852  0.207774   28.4606   
2021            4230      4141      27.6336    28.473234  27.960248  0.196539   27.890499 
2022            4230      4141      29.921432  30.754467  30.345126  0.20125    30.334066 
2023            4230      4141      28.215334  29.242533  28.852908  0.257069   28.9002