Dear Stata users,

I want to use graph hbar to draw a population pyramid. Regular procedure is to generate a variable that equals to its negative (for example negmales in my dataset). When I graph hbar and add labels to bars, labels that in left are unsurprisingly draw as negative numbers. So my question is how to make them be drawn as positive numbers. The following example is a modified dataset borrowed from Lawrence Hamilton's Statistics with STATA (sic).

Code:
clear
input int year byte agegroup float(negmales females)
2006 1 -7818 7560
2006 2 -3487 3396
2006 3 -2917 2710
2006 4 -5011 4768
2006 5 -3489 2949
2006 6 -1902 1711
2006 7  -921 1032
2006 8  -259  404
2006 9   -13   50
end
label values agegroup age
label def age 1 "0~16", modify
label def age 2 "17~25", modify
label def age 3 "26~35", modify
label def age 4 "36~45", modify
label def age 5 "46~55", modify
label def age 6 "56~65", modify
label def age 7 "66~75", modify
label def age 8 "76~85", modify
label def age 9 "85~91", modify

graph hbar (sum) negmales females, over(agegroup, descending gap(0)) ylabel(-10000 "10000" -5000 "5000" 0 5000 10000) stack blabel(bar)
Array