Search Comma Separated List for Nearest Value

Hello,
I have a project that contains comma separated lists. I need to search the list for the closest value without going over a target value. (i.e. if the target value is 16 and the list contains 5, 20, 15, 17, 32 then it should return 15)

My actual workbook contains too many comma separated lists for it to be feasible to break them down into columns and go about it that way.