  We have combined X-ray observations from Chandra with Sunyaev-Zel'dovich (SZ)
effect data from Planck and Bolocam to measure intra-cluster medium pressure
profiles from 0.03R$_{500}$ $\le$ R $\le$ 5R$_{500}$ for a sample of 21 low-$z$
galaxy clusters with a median redshift $\langle z \rangle = 0.08$ and a median
mass $\langle \textrm{M}_{500} \rangle = 6.1 \times 10^{14}$ M$_{\odot}$ and a
sample of 19 mid-$z$ galaxy clusters with $\langle z \rangle = 0.50$ and
$\langle \textrm{M}_{500} \rangle = 10.6 \times 10^{14}$ M$_{\odot}$. The mean
scaled pressure in the low-$z$ sample is lower at small radii and higher at
large radii, a trend that is accurately reproduced in similarly selected
samples from The300 simulations. This difference appears to be primarily due to
dynamical state at small radii, evolution at intermediate radii, and a
combination of evolution and mass dependence at large radii. Furthermore, the
overall flattening of the mean scaled pressure profile in the low-$z$ sample
compared to the mid-$z$ sample is consistent with expectations due to
differences in mass accretion rate and the fractional impact of feedback
mechanisms. In agreement with previous studies, the fractional scatter about
the mean scaled pressure profile reaches a minimum of $\simeq 20$ per cent near
0.5R$_{500}$. This scatter is consistent between the low-$z$ and mid-$z$
samples at all radii, suggesting it is not strongly impacted by sample
selection, and this general behavior is reproduced in The300 simulations.
Finally, analytic functions that approximately describe the mass and redshift
trends in mean pressure profile shape are provided.
