\label{fig:TLEPUpgrade} The TLEP luminosity as a function of the centre-of-mass energy (red line), summed over the four IPs, when upgraded to $\sqrt{s}=500$~GeV, in units of $10^{34}~\cms$. For illustration, the baseline luminosities for the two linear collider projects, ILC (blue line) and CLIC (green line), are also indicated.