with tmp as (
	SELECT
	IMT.PORT_CODE
	, PORT.PORT_NAME
	, sum(case when GRP.GROUP_CODE = '120' and IMT.KIND_CODE = '110' then IMT.AMT else 0 end) as total_in
	, sum(case when GRP.GROUP_CODE = '120' and IMT.KIND_CODE = '120' then IMT.AMT else 0 end) as total_out
	FROM IMMIGRATION as IMT
		INNER JOIN GRP ON IMT.GROUP_CODE = GRP.GROUP_CODE
		INNER JOIN PORT ON IMT.PORT_CODE = PORT.PORT_CODE
	GROUP BY 1,2
)
SELECT
	t1.PORT_CODE as '港コード'
	, t1.PORT_NAME as '港名'
	, t1.total_in as '入国者数'
	, t1.total_out as '出国者数'
	, t1.total_in - t1.total_out as '差分'
FROM tmp as t1
WHERE t1.total_in > t1.total_out
ORDER BY 5 desc, 1
;