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\begin{document}

\begin{table}[h!]
\caption{Results of AFSA and GWA for K=10 under certain condition }\label{tbl2}

  \centering
    \begin{tabularx}{\textwidth}{|b|bbbm|bbbm|}

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    % after \\: \hline or \cline{col1-col2} \cline{col3-col4} ...
    \multirow{3}{3cm}{Risk \\aversion\\ coefficient}&\multicolumn{4}{c}{AFSA}&\multicolumn{4}{|c|}{GWA}\\
    \cline{2-9}
    &\multirow{2}{4cm}{Total \\portfolio \\return\\}&\multirow{2}{4cm}{Total\\ portfolio \\risk\\}&Objective value&Solution time&\multirow{2}{4cm}{Total\\ portfolio\\ return\\} &\multirow{2}{4cm}{Total\\ portfolio\\ risk\\}&Objective value&Solution time\\

    \cline{1-9}
0.0&1.31&0.72&-58.13&1.27&1.30&0.70&-56.10&0.96\\
0.1&1.21&0.69&-50.29&1.40&1.20&0.60&-50.19&1.40\\
0.2&1.19&0.63&-40.59&2.16&1.18&0.50&-40.05&3.19\\
0.3&1.09&0.55&-34.56&3.76&1.08&0.47&-32.10&4.22\\
0.4&1.07&0.52&-27.42&5.49&1.06&0.45&-26.27&5.97\\
0.5&1.03&0.48&-19.05&6.19&1.02&0.44&-18.88&7.62\\
0.6&0.97&0.44&-12.11&10.37&0.96&0.44&-11.06&8.19\\
0.7&0.88&0.44&-4.52&11.29&0.88&0.44&-4.23&10.07\\
0.8&0.88&0.44&2.10&13.96&0.88&0.44&2.91&11.27\\
0.9&0.82&0.42&8.90&15.79&0.81&0.42&8.71&13.96\\
1.0&0.81&0.40&14.24&18.96&0.80&0.40&14.14&15.84\\
Mean&1.02&0.52&-20.04&8.24&1.01&0.48&-19.53&7.52\\
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 \end{table}




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