How are establishments linked over time?
The linkage process matches establishments’ unique State Employment Security Agency (SESA) identification numbers (SESA-ID). Between 95 to 97 percent of establishments identified as continuous from quarter to quarter are matched by SESA-ID. The rest are linked in one of three ways. The first method uses predecessor and successor information, identified by the States, which relates records with different SESA-IDs across quarters. Predecessor and successor relations can come about for a variety of reasons, including a change in ownership, a firm restructuring, or a UI account restructuring. If a match cannot be attained in this manner, a probability-based match is used. This match attempts to identify two establishments with different SESA-IDs as continuous. The match is based upon comparisons such as the same name, address, and phone number. Finally, an analyst examines unmatched records individually and forces a match, if possible.
