Global trends for our parallax zero points as a function of the three quantities defining the L21 correction. Top: Median parallax offsets estimated from asteroseismology (E20+APOGEE) as a function of the sine of ecliptic latitude. Kepler and TESS are plotted as white and black symbols, respectively. The coloured symbols correspond to the various K2 fields, and follow the colour scheme adopted in Fig. 1. Middle and bottom: Median parallax difference binned by G magnitude (middle) and effective wavenumber (bottom). Kepler and TESS are plotted as black solid and dashed lines, respectively. The median uncertainty on the parallax difference is shown in the lower part of each panel. C15 does not appear in the two bottom panels as there are not enough stars to bin in G and ν_eff.