\begin{table} %T3 \caption{\label{fittingcomb}Best-fitting parameters for the joint CPL and BPL fits to all six sub-regions of 3C~449.} \small %\centering \par \begin{tabular}{c c c c c c c c c c c c c} \hline\hline\noalign{\smallskip} & \multicolumn{5}{c} {Best fit} & & \multicolumn{3}{c} {Min slope}& \multicolumn{3}{c} {Max slope} \\ \noalign{\smallskip} & $q$ &$f_{\rm max}$ & & $\chi^2$ & & $q^{\rm -}$ & $f_{\rm max}$ & & $q^{\rm +}$ & $f_{\rm max}$ & \\ \noalign{\smallskip} joint CPL & 2.68 & 1.67 & & 33.5 & & 2.55 & 1.30 & & 2.81 & 2.00 & \\ \hline &\multicolumn{5}{c} {Best fit} & & \multicolumn{3}{c} {Min slope} & \multicolumn{3}{c} {Max slope} \\\noalign{\smallskip} & $q_l$ &$f_{\rm b}$ & $q_h$ & $\chi^2$ & & $q_l^{\rm -}$ & $f_{\rm b}$ & $q_h^{\rm -}$ & $q_l^{\rm +}$ & $f_{\rm b}$ & $q_l^{\rm +}$ \\ \noalign{\smallskip} joint BPL & 2.07 & 0.031 & 2.97 & 17.7 & & 1.99 & 0.044 & 2.91 & 2.17 & 0.021 & 3.09 &\\ \hline \end{tabular} \tablefoot{Lower and upper limits are quoted at $\sim$90\% confidence. The values of $q$ and $f_{\rm max}$ for the joint CPL fit and $q_h$, $q_l$ and $f_{\rm b}$ for the joint BPL fit are the same for all sub-regions, while the normalizations are varied to minimize the overall $\chi^2$. In the joint BPL fit, the maximum frequency is fixed at $f_{\rm max}= 1.67$~arcsec$^{-1}$.} \end{table}