Mass flux as a function of X-ray surface flux. The filled and unfilled blue triangles show the upper limits on the mass-loss rate per unit surface area we find in this work for the stars with no magnetic field measurements, using respectively high and mean estimates for the magnetic field. The filled red triangles represent the stars for which the large-scale magnetic field is known. The mass flux is in units of the solar mass flux, which we take to be 2 × 10⁻¹⁴ M_⊙ yr⁻¹/(4π R${}_{\odot }^2)$. The black symbols show mass-loss rate measurements and estimates from Lim & White (1996), Lim et al. (1996), Gaidos et al. (2000), Wood et al. (2001, 2002, 2005, 2014), Wood & Linsky (2010), Wood (2018), Jardine & Collier Cameron (2019), and Finley et al. (2019). No error bars are plotted for the stellar literature values as the uncertainties are not reported in the corresponding papers.