Wind structure parameters versus mass-loss rate. Diamonds correspond to stars of our sample. We also show the samples of Brands et al. (2022, squares) and Hawcroft et al. (2024a, circles). The luminosity classes of the latter two samples are indicated with different shades. We find a positive correlation between the interclump density (f_ic) and the mass-loss rate, but find no correlations with any stellar parameter or mass-loss rate for the other wind-clumping parameters.