|tag of unknown meaning and unclear purpose added by imports from official US sources|
|Used on these elements|
|Status: in use|
|Tools for this tag|
Meaning of that tag is unclear and it is dubious whatever it should be present on any object.
In http://www2.census.gov/geo/pdfs/maps-data/data/tiger/tgrshp2008/TGRSHP08.pdf it is defined as "Current functional status" and restricted to be string of length 1.
See https://lists.openstreetmap.org/pipermail/talk-us/2019-March/019389.html for discussion of it meaning.