StataTex Blog

For plotting the relative importance of (e.g.) input shares, it can be useful to stack them in a figure. In my specific problem, I wanted to show the development of low-, medium-, and high-skilled labour inputs, relative to all labour inputs over time. Since the three shares obviously sum up to 1, I wanted to have a figure like this:

In order to get a figures like this, follow these steps:
1) generate three variables (here: ls, ms, hs) which sum up to one. You need to sum up the shares so that: ls=ls; ms=ls+ms; hs=ls+ms+hs=1

2) Use the following code in Stata

twoway (area hs year, color(gs13)) (area ms year, color(gs9)) (area ls year, color(gs4)), xlabel(1970 (5) 2005, alternate) ylabel(0 (25) 100, alternate nogrid val) xtitle("") text(10 1980 "{bf:low-skilled}") text(50 1990 "{bf:medium-skilled}") text(90 1995 "{bf:high-skilled}") by(industry, legend(off))


The stacked graph is essentially an overlay of three separate layers of the figure (one for each input). Worth mentioning is the following command: text(10 1980  "{bf:low-skilled}") which puts text into the figure.