Rest-frame Fe Kα equivalent width function at z = 0.05, 0.50, 1.0, and 1.5. The solid line plots the function assuming a constant R = 1, while the dashed line follows the strong light-bending prescription. The peaks in the curves indicate EWs that are most common at that redshift. For the R = 1 model, the peaks correspond to neutral Fe Kα lines (at ~110 eV) and ionized reflection (at ~300 eV). In the light-bending model, the lines are always produced by neutral iron. The roll-over at low EWs in the light-bending model at z = 0.05 corresponds to ionized Fe Kα lines from luminous quasars (which have very low space density at that redshift). The average EWs for both models are also indicated in the plots. The curves have been smoothed for clarity.