st:graph mean with missing groups

[Amanda Fu <mandy.fu1@gmail.com>]

Hi All,

I am stuck with drawing a graph about means of a test score variable
by groups. The problem is caused by there are some "empty" groups.

The variable "score" range from 0 to 100. I cut it into 10 bands : 0,
1-10, 11-20,21-30,...,91-100. I create a new variable "score_percent"
indicates the percent for the share of observations in each band.
The data set is like:
id   score   score_percent
1      32           3.8         (Totally 3.8% observations have scores
between 31-40)
2      89         23.4
3      67         16.5
...................
I tried to use the following command to create a graph for mean level
of test scores:
.twoway connected   score_percent    score ,xlabel(0(10)100)
-------------------------
However, in the data set none observations have scores from 11-20. So
this is an empty band. The value of "score_percent" for this band
should be 0. But if I use the above command to draw the graph, the
connected line will skip the empty band and directly jump to the next
point (it is like, along the x-axis there are band 0-10, 21-30,.....).
What I wanted is to give the empty band with percent share is 0.
I wonder if someone can give me some suggestion how to fix this. Thank you!

Amanda
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