CMDs in δ₄, y₀ for the RGBs of the nine GCs, with the RGB bump level indicated by an arrow. The blue and red curves, stopped one magnitude brighter than the RGB bump, where the statistics begins to be too scarce, are polynomials describing the populations, drawn according to the distributions of P and IE stars in Fig. 5. For NGC 6752 the distribution of stars is trimodal (see text and next figure) and an intermediate (green) line is drawn.