Volume-weighted density distribution of gas (left) and stars (right) in the radial (upper row) and vertical (lower row, averaged from 8 to 9 kpc) directions for F3000HD (blue) and MW3000HD (red) averaged from 2450 to 2550 Myr. Shaded regions indicate the 16th to 84th percentile. The density distributions generating our adopted external potentials are indicated in grey, dotted for the flat potential and dash-dotted for the Milky Way model. In the radial direction, we took into account mass up to z = ±50 pc.