Vacuumdb on a table

Hi,

The first table in the following query resulted in age(c.relfrozenxid) = 148795396. But when I manually run vacuumdb command (vacuumdb -d db1 -t tab1) on that table it is not lowering the relfrozenxid. There is no indication in the pglog that vacuumdb failed.

SELECT c.oid::regclass

    , age(c.relfrozenxid)

    , pg_size_pretty(pg_total_relation_size(c.oid))

FROM pg_class c

JOIN pg_namespace n on c.relnamespace = n.oid

WHERE relkind IN ('r', 't', 'm')

AND n.nspname NOT IN ('pg_toast')

ORDER BY 2 DESC ;

I am wondering why vacuumdb is unable to lower relfrozenxid on this table? It seems to work on other tables though.

Thank you!