Ṗ_OF/Ṗ_AGN of molecular and nuclear winds (UFOs) vs. the wind velocity for APM 08279 (red symbols), Mrk 231 (black circles, from Feruglio et al. 2015) and IRAS 11119 (black triangle, from Tombesi et al. 2015). UFOs are at > 10⁴ km s^-1. Molecular outflows are at velocities ~ 1000 km s^-1 for each source. For APM 08279 the two values of Ṗ_OF listed in Table 3 are used to derive Ṗ_OF/Ṗ_AGN. The oblique dashed lines show the expectation for energy conserving flows; the horizontal dashed line shows that for momentum-conserving flows. The error bar shows the typical statistical error.