SELECT
	IMT_1.PORT_CODE
	, PORT.PORT_NAME
	, IMT_1.AMT as '入国者数'
	, IMT_2.AMT as '出国者数'
	, IMT_1.AMT - IMT_2.AMT as '差分'
FROM IMMIGRATION as IMT_1
	INNER JOIN IMMIGRATION as IMT_2
		on IMT_1.PORT_CODE = IMT_2.PORT_CODE
		and IMT_1.GROUP_CODE = IMT_2.GROUP_CODE
		and IMT_2.KIND_CODE = '120'
	INNER JOIN GRP ON IMT_1.GROUP_CODE = GRP.GROUP_CODE
	INNER JOIN PORT ON IMT_1.PORT_CODE = PORT.PORT_CODE
WHERE 
	IMT_1.GROUP_CODE = '120'
	AND IMT_1.KIND_CODE = '110'
	AND IMT_1.AMT > IMT_2.AMT
GROUP BY 1,2
ORDER BY 5 desc, 1