Gas pressure P_g, 0 (upper left panel) at the inner boundary (z₀ = 1 kpc) of the flux tube for Model W (full line) and Model H (dashed line) as a function of time including the feedback by galactic wind loss. The CR pressure P_c, 0 (upper panel right) is lower by about a factor of 10 compared to the gas pressure. All boundary values decrease between the SN explosions. After 6 × 10⁶ yr, when the last SN exploded, the boundary values get monotonically smaller, caused by the outflow from the SB. Lower panel (left): exhibits the mass loss by the galactic wind, which reaches a maximum rate around 3.2 × 10⁻³ M_⊙ yr⁻¹ for Model W and 4.1 × 10⁻³ M_⊙ yr⁻¹ for Model H. In both models the maximum outflow velocity u₀ (lower panel right) is reached at the last SN explosion.