In 2018 the CPI program changed the areas and area codes for which it provides data. Some areas were added, some discontinued, and some have different geographic codes. To accommodate this, we added an areatype 41 (2018 CPI Areas) to the recommended values and a new set of sub-national area codes to the geog table. If you load the CPIPLUS data from the ARC or CPI data for you state from the BLS you will need to make changes to the lookup tables.
For more details on the change, see the BLS documentation.