WITH Y20 AS(
    SELECT TOTAL_AMT,PF_CODE
    FROM POPU_TRANSITION
    WHERE SURVEY_YEAR = 2020
    GROUP BY PF_CODE)
    ,Y15 AS(
    SELECT TOTAL_AMT,PF_CODE
    FROM POPU_TRANSITION
    WHERE SURVEY_YEAR = 2015
    GROUP BY PF_CODE)

SELECT 
DISTINCT PO.PF_CODE "都道府県コード",
PRE.PF_NAME "都道府県名",
Y15.TOTAL_AMT "総人口2015年",
Y20.TOTAL_AMT "総人口2020年",
ROUND((100.0*Y20.TOTAL_AMT/Y15.TOTAL_AMT),0) "人口増加率"
FROM POPU_TRANSITION PO JOIN PREFECTURE PRE ON PO.PF_CODE = PRE.PF_CODE
JOIN Y15 ON PO.PF_CODE = Y15.PF_CODE
JOIN Y20 ON PO.PF_CODE = Y20.PF_CODE
WHERE Y20.TOTAL_AMT > Y15.TOTAL_AMT

ORDER BY "人口増加率" DESC,"都道府県コード"