Redshift evolution of the width of the rest frame RM distribution (w_RM,rest) of different subsets of galaxies. A curved power law can be fitted to each group. The error bars are from bootstrapping, a: quenched and star-forming galaxies. At high ɀ we only have a few (<10) quenched galaxies, which makes it difficult to obtain a good fit. b: different stellar mass bins, c: different inclinations, d: sightlines with different b_offset.