  The most common observed feature of the X-ray outflows in active galactic
nuclei (AGN) is their broad ionization distribution spanning up to $\sim$ 5
orders of magnitude in ionization levels. This feature is quantified in terms
of absorption measure distribution (AMD), defined as the distribution of column
density with the ionization parameter. Recently, the photoionization models
with constant pressure assumption are shown to well reproduce the observed
shape of AMD. However, there exist inconsistencies in the normalization and the
position of discontinuities presented in the AMD shape between the observation
and model. In this work, we show that AMD normalization differs by one order of
magnitude depending on the shape of ionizing spectral energy distribution
(SED).
