Various thoughts in addition to other suggestions: 
I did once suggest a percent format to StataCorp -- without eliciting
any interest. 
If your bar chart is really a relative of a histogram, then -histogram,
discrete percent- may be of help. 
The program -mylabels- on SSC supports some label fixes of this type. It
doesn't support showing "%" on every label, which I regard as
unnecessarily repetitious, but it could be cloned to permit that. 
There is a generic discussion at 
SJ-8-1  gr0032  . . . . . . .  Stata tip 59: Plotting on any transformed
scale
        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N.
J. Cox
        Q1/08   SJ 8(1):142--145                                 (no
commands)
        tip on how to graph data on a transformed scale
Of various suggestions in this thread, Svend's is closest to what I
would do given such a client. 
Nick
[email protected] 
Richard Goldstein
I need to produce a sizable number of bar graphs for a client.  The 
client wants the y-axis to be labeled as, e.g., "15%" rather than as, 
e.g., .15.  The range of proportions for these graphs varies quite a bit
(from a max of less than .05 to a max of over .2) so I don't want to 
force them all to be the same.
After seeing a graph, it is easy enough to use the ylabel option to get 
what I want.  Given that I am generally willing to live with Stata's 
automatic choice of tick marks, is there a way to automatically get 
labels in the form I want (e.g., "15%") rather than the way Stata wants 
(e.g., .15)?
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