Three toy model jets simulated using the semianalytical code of Hardcastle (2018) with powers Q = 10³⁵ W (circles), Q = 10³⁶ W (squares), and Q = 10³⁷ W (stars). Panel (a) shows the evolution of 1.4 GHz luminosity with linear size colored by the jet age. Panel (b) shows the linear size growth as a function jet age, with the points colored by L _{1.4 GHz}. The red dashed line in panel (b) shows the 20 Myr typical lifetime of O-type stars.