with foreigner AS
  (
    select
      port_code
      , sum(case when kind_code = 110 then amt else 0 END) AS in_cnt
      , sum(case when kind_code = 120 then amt else 0 END) AS out_cnt
    from
      immigration
    where
      group_code = 120 --外国人
    group by
      1
  )  
			
select
  foreigner.port_code AS '港コード'
  , port_name      AS    '港名'
  , in_cnt         AS    '入国者数'
  , out_cnt        AS    '出国者数'
  , in_cnt-out_cnt AS    '差分'
fROM
  foreigner
inner join
  port using(port_code)
where
  in_cnt > out_cnt
order by
  5 desc,1 desc