Colours of the superclusters (see text for details) by Pessev et al. (2008), indicated by circles with error bars, and Noël et al. (2013), indicated by squares with error bars. The horizontal error bars denote the age bins covered by each supercluster. Predictions from models for Z = 0.008 (red dots) and Z = 0.004 (blue three-pointed stars) with a number of AGB stars corresponding to total masses a few times 10⁵M_⊙ are shown for comparison.