Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            590       553       29.923515  30.286451  30.212977  0.06487    30.223354 
2008            590       553       29.466742  30.009129  29.842935  0.108995   29.870323 
2009            590       553       30.157129  30.781902  30.634044  0.132499   30.680355 
2010            590       553       30.323097  30.873549  30.725416  0.117254   30.740969 
2011            590       553       30.51129   30.809807  30.705933  0.06813    30.721935 
2012            590       553       29.685194  30.395161  30.228079  0.144996   30.275742 
2013            590       553       29.481129  29.842194  29.718906  0.06938    29.722967 
2014            590       553       30.647259  31.274515  31.023417  0.117209   31.049032 
2015            590       553       30.511387  30.998032  30.814426  0.101581   30.813904 
2016            590       553       29.912613  30.512516  30.335327  0.140093   30.386614 
2017            590       553       30.183064  30.833355  30.633425  0.148291   30.68329  
2018            590       553       30.017     30.546741  30.436762  0.100417   30.468065 
2019            590       553       30.065935  30.521904  30.356414  0.126737   30.367128 
2020            590       553       30.067291  30.881323  30.528297  0.203501   30.549484 
2021            590       553       30.00058   30.746161  30.495385  0.138842   30.513453 
2022            590       553       30.300194  30.745161  30.593981  0.103147   30.627903 
2023            590       553       30.671516  31.351387  31.22252   0.167569   31.291355