

\begin{longtable}{|r|r|r|r|}\hline
   \multicolumn{4}{|c|}{Extreme Observations}\\\hline
   \multicolumn{2}{|c|}{Lowest} &    \multicolumn{2}{|c|}{Highest}\\\hline
   Value &    Obs &    Value &    Obs\\\hline
\endhead
   4.0 &    23 &    4.8 &    27\\\hline
   4.3 &    30 &    5.1 &    22\\\hline
   4.3 &    21 &    5.2 &    29\\\hline
   4.4 &    25 &    6.0 &    24\\\hline
   4.6 &    26 &    6.4 &    28\\\hline
\end{longtable}

