  We present a systematic analysis of all archival Chandra observations of the
soft-gamma repeater SGR 0526-66. Our results show that the X-ray flux of SGR
0526-66 decayed by about 20% between 2000 and 2009. We employ physically
motivated X-ray spectral models and determine the effective temperature and the
strength of the magnetic field at the surface as kT = 0.354_{-0.024}^{+0.031}
keV and B = (3.73^{+0.16}_{-0.08})x10^{14} G, respectively. We find that the
effective temperature remains constant within the statistical uncertainties and
attribute the decrease in the source flux to a decrease in the emitting radius.
We also perform timing analysis to measure the evolution of the spin period and
the period derivative over the nine year interval. We find a period derivative
of \.P = (4.0 +/- 0.5)x10^{-11} ss^{-1}, which allows us to infer the dipole
magnetic field strength and compare it with the one determined
spectroscopically. Finally, we compare the effective temperature of SGR 0526-66
with the expected cooling trends from magnetized neutron stars and suggest an
initial magnetic field strength of 10^{15-16} G for the source.
