Labeliing of Bar graph in X axis

I have a simple bar graph with the Y- axis measuring vertically in units and
the X-axis a series of bars that show month 2004 then same month 2005
repeated from november to july. The legend places the months/ year with a
colour code BUT I want to have the actual bar displaying the 2004 November ,
then next bar 2005 November and so forth through 2004/ 2005 July. At this
stage there is no actual labelling of each bar except for a legend of colours
and the Month/year detail.

Any help please.
Mike