The minimum corona observed with the Mark-III K-coronameter
during the Whole Sun Month is compared with observations
taken in June 1991 close to the last solar maximum.
For both periods the three-dimensional structure of the
electron density is reconstructed from coronagraph images
covering a full rotation period of the Sun.  This is
accomplished by using methods of computer tomography 
specially adapted for the inversion of coronagraph images.  
The global structure is compared with a potential-field
source-surface expansion of the photospheric magnetic
field.  The result affirms the model of a streamer belt
around the Sun, however, with remarkable longitudinal 
density variations.  A deviation between the magnetic
field extrapolation and the reconstructed density
enhancements occurs in the vicinity of an intense
bipolar magnetic region.  It can probably be attributed to 
the presence of non-negligible currents in this 
region.  We derive scale-height temperatures of 1.3 to 1.9 
degrees Kelvin from selected radial density profiles 
for the Whole Sun Month.