Mean Galactocentric radial velocity as a function of distance from the Sun. Only the distances corresponding to the full sample highest Bayesian confidence interval (HDI) are considered. Dotted black lines correspond to the 68% HDI and full lines corresponds to the 50% HDI. In grey the confidence interval at 1 sigma obtained by bootstrap. The vertical dotted blue lines indicate the distance corresponding to the centre of a bar with R₀ = 7.6 kpc and φ_bar = 26°, as represented in Fig. 13.