  Recent advances in observations have provided a wealth of measurements of the
expansions of outflows in galactic discs out to large radii in a variety of
galactic hosts. To provide an updated baseline for the interpretation of such
data, and to assess to what extent the present status of the modeling is
consistent with the existing observations, we provide a compact two-dimensional
description for the expansion of AGN-driven shocks in realistic galactic discs
with exponential gas density profiles in a disc geometry. We derive solutions
for the outflow expansion and the mass outflow rates in different directions
with respect to the plane of the disc. These are expressed in terms of the
global properties of the host galaxy and of the central AGN to allow for an
easy and direct comparison with existing observations in a variety of galactic
hosts with measured properties, and out to distances $\sim 10$ kpc from the
centre. The results are compared with a state-of-the-art compilation of
observed outflows in 19 galaxies with different measured gas and dynamical
mass, allowing for a detailed, one-by-one comparison with the model
predictions. The agreement we obtain for a wide range of host galaxy gas mass
and AGN bolometric luminosity provides a quantitative systematic test for the
modeling of AGN-driven outflows in galactic discs. We also consider a larger
sample of galaxies with no reliable measurements of the gas and dynamical mass.
In this case we perform a comparison of the model predictions for different
bins of AGN luminosities assuming values for the gas mass and dynamical mass
derived from scaling relations. The encouraging, quantitative agreement of the
model predictions with a wide set of existing observations constitutes a
baseline for the interpretation of forthcoming data, and for a more detailed
treatment of AGN feedback in galaxy formation models.
