Hi, I am trying to represent my data in a stacked chart. I have data on export and import. What I am trying to show is the percentage of the observations in which i have observations for both export and import, either export or import and no observations at all. To be more precise, I'm trying to visualise it in a similar manner as Helpman et al. (2008) does in their "Estimating Trade Flows: Trading Partners and Trading Volumes", which looks like this
Array

I have created two three variables. TradeBoth is = 1 given that both export and import has a positive value. TradeOne is 1 given that one of export or import has a positive value, but the other one is unobserved. A variable "missing" that is 1 given that both export and import is missing. If these variables are not 1, then I have them as "."


I tried initially to run something like this to then built upon it. However, I can't get percent to work.

graph bar (percent) TradeBoth TradeOne missing, over(year) stack title("Data distribution")
Im trying to do this through year 1996 to 2017.

Thank you for any helpful answers!

Sincerely,
Jonathan