st: space between plots when using "graph combine"

[Maria Ana Vitorino <vitorino@wharton.upenn.edu>]

I have a question regarding the graph regions. I have 4 square plots  
that I want to put in the same figure. If we look at the plots  
individually, the figures are square (including the margins around the  
plot itself). But when I combine them the areas around the plots  
become rectangles.  Below is an example (I used colors so that it's  
easier to see what I'm trying to explain). Any suggestions on how to  
make the final combined plot also a square without wasting so much  
space to the left and to the right of the plots?
Thanks!
Ana


sysuse auto, clear
scatter mpg weight, aspect(1) xsize(5) ysize(5)  
graphregion(color(erose)) plotregion(margin(zero)) name(fig1, replace)
scatter mpg weight, aspect(1) xsize(5) ysize(5)  
graphregion(color(blue)) plotregion(margin(zero)) name(fig2, replace)
graph combine  fig1 fig2 fig2 fig1, saving(figcombo,  replace)

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