U.S. census block number (15 digits).
-=item censusyear
-
-The year of the census map where the block appeared or was last verified.
-
=back
=head1 METHODS
$self->ut_numbern('blocknum')
|| $self->ut_number('zonenum')
|| $self->ut_number('censusblock')
- || $self->ut_number('censusyear')
;
return $error if $error;