I want to change the attached graph so that instead of appearing as two sub-figures, there is just one plot with three pairs of bars, corresponding to:

same and vaccinated
same and not vaccinated
decrease and vaccinated
decrease and not vaccinated
increase and vaccinated
increase and not vaccinated

My basic code to produce the graph right now is
Code:
 graph hbar, by(vaccinated) over(prob_infection_change_sign)
.

How could I adjust this to get what I want?

(Unfortunately, I can't share my actual data here as it is somewhat confidential. I've changed the names of variables to an unrelated topic. )