Year            Count     Valid     Min        Max        Mean       Stdev      Median
2007            560       525       17.56275   18.053286  17.869451  0.128258   17.912357 
2008            560       525       17.751862  18.172483  18.028068  0.098644   18.054035 
2009            560       525       17.754999  18.587465  18.207877  0.205841   18.167858 
2010            560       525       14.589     15.261822  15.007721  0.162737   15.074107 
2011            560       525       16.2805    17.331715  16.910498  0.270503   16.880501 
2012            560       525       16.75631   17.534723  17.18514   0.197293   17.230103 
2013            560       525       16.665607  17.281286  17.038899  0.175886   17.051537 
2014            560       525       16.493036  17.10725   16.858715  0.14492    16.884857 
2015            560       525       16.457644  17.191679  16.800782  0.196558   16.769571 
2016            560       525       16.39431   17.131172  16.808631  0.207188   16.814379 
2017            560       525       18.149071  18.759394  18.470058  0.173602   18.489679 
2018            560       525       17.628963  18.546072  18.19415   0.229468   18.25775  
2019            560       525       15.445464  16.305536  15.962649  0.217851   16.051537 
2020            560       525       15.065104  16.296759  15.597238  0.334918   15.550655 
2021            560       525       13.803     14.967115  14.315791  0.316675   14.259039 
2022            560       525       12.525536  13.796607  13.189668  0.325904   13.238464 
2023            560       525       15.053392  15.8345    15.481618  0.201369   15.537642