I am asking to the experts the following problem that I am unable to
solve.
I have the following worksheet:
Classes:_______Lecturer1(hours):________Lecturer 2(hours):
macro_______________20______________________30
micro_______________40______________________50
literat._____________0______________________20

I need to show with stack bars that lecturer 1 (first stack bar) has
20+40 hours and the label of any piece of the bar should have the name
of the classes. So the piece of the bar with height 20 should contain
the text "macro", the other piece of height 40 the text "micro", etc.

With Excel the latter can be obtained by showing the values of series.
Yet the chart shown contain also the labels of the series that have no
value in that column. Example: in the first stack Column on the top
there is also the text "literat." though there is any piece of
"literat." column in it.
How do I avoid (apart to cancel it manually) that the label "literat."
(or for the matter of any other class) appear in those columns that do
not contemplate hours of that class?
Thanks
AR