Using maths functions in embeded data

Hello, In our survey we will ask for participant ethnicity, and then branch to show only 2x of 7 specific ethnicity blocks in order of priority (for ethnicity A,B,C,D,E,F,G), and a catch-all ethnicity block (for ethnicity H to Z). E.g. If a user identifies that they are ethnicity (A,C,M), they would only see blocks (A,C). If a user identifies (C,P,Q) they would see block (C) and the catch-all. I've been trying to identify a good logic solution and I thought about incrementing an embedded field (Ethnicity_count). I would like to use maths operations in the survey flow, but I've not been able to get it working using the following: set embeded data ${e://Field/Ethnicity_count} = 0 IF ethnicity = (A) THEN show block (A) AND set embeded data ${e://Field/Ethnicity_count} = ${e://Field/Ethnicity_count + 1} Does this work in Qualtrics? Can anyone give me some tips, or another solution? I've tried unsuccessfully with Quotas, and I believe that quota's are more aimed at data across all participants, not individual participants. Thanks Dan