Derivation
variable: stillmardate (table[s]: all_spouse_pairs_full [derived table])
variable: rmardate (table[s]: all_spouse_pairs_full [derived table])
variable: rsepdate (table[s]: all_spouse_pairs_full [derived table])
The latest date either couple report being married to this partner is used first (i.e. the interview date when the partnership first reported when they are married to them). It is updated to the latest co-residency date if this is later. After all the dates have been finalised this date is removed if sepdate is available.