Left: magnetic energy density versus kinetic energy density for the 113 sources in the sample with a good fitting result, with colour representing their synchrotron peak frequency. For comparison, the results obtained by Tavecchio & Ghisellini (2016) (as black triangles), Nievas Rosillo et al. (2022) (as orange crosses), and Zhao et al. (2024) (as grey circles) are shown. The dashed grey lines represent the lines for U_B = 10² × U_e, U_B = U_e (equipartition), U_B = 10⁻² × U_e, and U_B = 10⁻⁴ × U_e. Right: distribution of the ratio of magnetic energy density to kinetic energy density (U_B/U_e) for three different samples, corresponding to three ranges of synchrotron peak frequency: ${\nu }_{\text{sync\hspace{0.17em}}}^{\text{peak\hspace{0.17em}}}\le 6.7\times {10}^{16}\mathrm{H}\mathrm{z}$ (top), $6.7\times {10}^{16}\mathrm{H}\mathrm{z}<{\nu }_{\text{sync\hspace{0.17em}}}^{\text{peak\hspace{0.17em}}}\le 4.3\times {10}^{17}\mathrm{H}\mathrm{z}$ (middle), and ${\nu }_{\text{sync\hspace{0.17em}}}^{\text{peak\hspace{0.17em}}}>4.3\times {10}^{17}\mathrm{H}\mathrm{z}$ (bottom).