Numbers of high-redshift AGN, N(>z), expected in the soft band for the extragalactic sky after four years. The thick solid black curve shows the prediction based on the default XLF model. Also shown are predictions for the XLF model of Miyaji et al. (2000, Table 3), Hasinger et al. (2005, Table 5, without the exponential redshift cutoff, dotted curve), and Ebrero et al. (2009). To obtain these curves we integrated the XLFs to the highest redshift of z = 7. All curves are rescaled to match the average source density computed with our default model (Sect. 3).