\begin{table}%t4
\caption{\label{table:4}Average (medians) of radio  emission duration, power, and solar wind pressure of Nan\c{c}ay non-Io DAM emissions for periods with FS, RS, HCS or no shocks within $\pm$1~day of the emission.} 
%\centering
\par
\begin{tabular}{c c c c c}   
\hline\hline \noalign{\smallskip}                
IP structure & $N$ & d$T$(min) & $P$ ($10^{-15}~{\rm W~m}^{-2})$ & $P_{\rm sw}$ (nPa) \\    
\hline                        
   FS  & 8 & 75(67) & 2.5(1.7) & 0.27(0.23) \\      
   RS  & 3 & 52(27) & 2.6(1.3) & 0.12(0.10) \\  
   HCS  & 3 & 120(107) & 1.1(0.9) & 0.27(0.23) \\  
   Multiple S  & 3 & 75(66) & 0.9(0.9) & 0.22(0.12) \\  
   None  & 20 & 70(62) & 1.9(1.4) & 0.06(0.03) \\  
  \hline                                   
\end{tabular}
\vspace*{5mm}
\end{table}