  Planck measurements of the cosmic microwave background power spectra find a
lower value of the Hubble constant $H_0$ and a higher value of the fractional
matter energy density $\Omega_{m0}$ for the concordance $\Lambda$CDM model, and
these results are in tension with other measurements. The {\em Planck} group
argued that the tension came either from some sources of unknown systematic
errors in some astrophysical measurements or the wrong $\Lambda$CDM model
applied in fitting the data. We studied the reason for the tension on $H_0$
from different measurements by considering two dynamical dark energy models. We
found that there is no tension between different data, the constraint on $H_0$
is almost unchanged for different dark energy models and the tension with the
local measurements remains when the error bar on $H_0$ is tightened to be
around 1. We argue that the tension on $H_0$ is not caused by the fitting
model.
