  The efficiencies of the gratings in the High Energy Transmission Grating
Spectrometer (HETGS) were updated using in-flight observations of bright
continuum sources. The procedure first involved verifying that fluxes obtained
from the +1 and -1 orders match, which checks that the contaminant model and
the CCD quantum efficiencies agree. Then the fluxes derived using the high
energy gratings (HEGs) were compared to those derived from the medium energy
gratings (MEGs). The flux ratio was fit to a low order polynomial, which was
allocated to the MEGs above 1 keV or the HEGs below 1 keV. The resultant
efficiencies were tested by examining fits to blazar spectra.
