wall panel designbs 5628

huangyhg

wall panel design:bs 5628
under the current revision of bs5628 part 1:2005 and annex b there is a requirement to include for additional eccentricity for slenderness effects in walls (or columns) where the slenderness ratio is less than or equal to 6.  
now this "additional eccentricity may be assumed to vary linearly from zero at top and bottom of the wall, to a value ea over the central fifth of the wall height" ('ea' is defined in the code bs 5628).
however,in the design software which i am using,it includes this eccentricity at the bottom of the wall as well.is this incorrect?
thanks in advance
please note that as i mentioned above:
"---additional eccentricity may be assumed to vary linearly from zero at top and bottom of the wall, to a value ea over the central fifth of the wall height---"
this statement is included in the annex b of bs 5628.