Yes. You would use the form:

pctin(expression,true) – This gives you the percent of respondents where expression equals true.

For expression, we’ll use the criteria you explained:

(x >= 1 and x <= 3) or (y >= 1 and y <= 3)

So that gives the following RB syntax:

pctin((x >= 1 and x <= 3) or (y >= 1 and y <= 3), true)