Parameter distributions of sample of 32 CSO sources combined with model predictions. Black symbols denote low-power CSOs (P_rad < 10^26.5 W Hz⁻¹) and red symbols represent high-power CSOs. The filled symbols are from the current study and the open symbols are from An & Baan (2012). Dashed red and black arrows relate to evolutionary trend for high- and low-power source distributions. The dashed blue lines in panels a, c, and f show the general power trend of the groups as a whole. The dashed blue line in panel b shows the expected survival threshold for low power sources. Panel a: Dashed red and black arrows denote the predicted P_rad ∝ D^2/3 adiabatic-loss-dominated evolution of a source with constant power, and the dashed blue line indicates the predicted power-size distribution: P_rad ∝ D⁴. Panel b: Dashed red and black arrows show the predicted inverse relationship between radio power and hotspot velocity: $P_{\mathrm{rad}}\propto V_{\mathrm{HS}}^{-1}$. Panel c: Hotspot velocity varies with the projected source size as V_HS ∝ D^−2/3. Panel d: Dashed arrows show the predicted evolutionary relation of P_rad ∝ T^2/5. Panels e and f: Dashed arrows indicate the predicted evolution following V_HS ∝ T^−2/5 and D ∝ T^3/5. Panels g and h: Relatively flat distribution of spectral index shows a slight steepening toward α = 1 with increasing kinematic age, T, and with projected source size, D.