Type of chart???
 

I would like to create a chart that plots a predicted value as a linr or
marker, lets say 60000 which could be classed as a total amount. This 60000
could correspond to 100% on the graph. At the same time I want the graph to
show monthly (%) figures, possibly in a one stacked bar type arrangement
which when totalled may add up to the predicted 60000 (100%) or may be under
or over, depending on how good my prediction was.

Is there such a graph to do this? The trouble I am finding at the moment is
that graph wants to consolidate both the monthly figures and the predicted
figure together to form 100%.

I would appreciate work through instructions if anyone has any.

Many thanks