Rotation curve of the Milky Way for Cepheids assuming R₀ = 8.09 kpc and Θ₀ = 233.6 km s⁻¹ (model 2). Red data points represent high-mass star-forming regions (Reid et al. 2014). Gray data points are taken from Sofue et al. (2009) and are rescaled to new (R₀, Θ₀) using formula ﹩{V}_{\mathrm{new}}={V}_{\mathrm{old}}+\tfrac{R}{8.0}\left({{\rm{\Theta }}}_{0}-200\right)﹩. Solid and dashed lines show the best-fitting models (linear and universal, respectively).