τ_dep vs. M_star for our sample and including data from the literature (Huang & Kauffmann 2014; Schruba et al. 2012; Bothwell et al. 2014). As in previous figures, the open triangles for Schruba et al. (2012) correspond to their compilation of data from the literature and the filled ones to their metal-poor dwarf observations. Our robust best-fit regression for these samples is shown as a dashed line; the dotted line corresponds to the slope for the COLDGASS galaxies alone (Huang & Kauffmann 2014).