Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            943       831       30.364645  30.684162  30.484059  0.068113   30.469452 
2008            943       831       28.996065  29.751871  29.341527  0.210911   29.300161 
2009            943       831       30.053484  30.389872  30.187398  0.080291   30.166967 
2010            943       831       30.490097  30.664064  30.56057   0.032914   30.56571  
2011            943       831       30.473969  30.820581  30.604599  0.068862   30.588324 
2012            943       831       29.860968  30.392517  30.102962  0.126047   30.069613 
2013            943       831       30.134806  30.458485  30.233484  0.058767   30.216904 
2014            943       831       30.402935  30.912903  30.677233  0.127027   30.634483 
2015            943       831       29.648451  30.102741  29.862457  0.104645   29.846903 
2016            943       831       30.240967  30.499065  30.366475  0.051581   30.361    
2017            943       831       30.558161  31.045549  30.797672  0.108989   30.769936 
2018            943       831       30.05942   30.634386  30.315912  0.138825   30.320065 
2019            943       831       29.50729   30.022549  29.78446   0.12173    29.824387 
2020            943       831       30.581451  30.961065  30.732074  0.128008   30.67042  
2021            943       831       30.179935  30.355129  30.251882  0.031681   30.255484 
2022            943       831       30.115612  30.554001  30.290025  0.087675   30.296354 
2023            943       831       31.570774  31.919743  31.749699  0.06327    31.746355