  A higher value of Hubble constant has been obtained from measurements with
nearby Type Ia supernovae, than that obtained at much higher redshift. With the
peculiar motions of their hosts, we find that the matter content at such low
redshift is only about 10% of that at much higher redshifts; such a low matter
density cannot be produced from density perturbations in the background of the
\Lambda CDM expansion. Recently the Planck team has reported a lower Hubble
constant and a higher matter content. We find that the dark energy density
increases with cosmic time, so that its equation-of-state parameter decreases
with cosmic time and is less than -1 at low redshift. Such dark energy
evolution is responsible for driving the super-accelerating expansion of the
universe. In this extended \Lambda CDM model, the cosmological redshift
represents time rather than radial coordinate, so that the universe complies to
the Copernican Principle.
