Hey all, I need some assistance regarding the appropriate data shaping and plot type to generate this simple plot (see attachment).

Basically all I'm trying to do is plot a change in a continuous outcome (6MWD) pre and post treatment for two different groups. The continuous scale is on the y axis and x axis only has two data points - pre-treatment and post-treatment (averages). I would like to have the lines connected for each treatment.

I've been fiddling with stata for awhile trying to figure this out but without avail. Anyone have any suggestions regarding the type of plot and how I need my data laid out? Thank you!