SELECT a.PF_CODE AS 都道府県コード
      ,a.PF_NAME AS 都道府県名
      ,b.Con2015 AS 総人口2015年
      ,b.Con2020 AS 総人口2020年
      ,ROUND(((b.Con2020 - b.Con2015) * 100.0)/b.Con2015 ,1) AS 人口増加率

From PREFECTURE a
INNER JOIN(
SELECT PF_CODE
      ,SUM(CASE WHEN SURVEY_YEAR = 2015 THEN TOTAL_AMT ELSE 0 END) AS Con2015
      ,SUM(CASE WHEN SURVEY_YEAR = 2020 THEN TOTAL_AMT ELSE 0 END) AS Con2020
FROM POPU_TRANSITION
WHERE SURVEY_YEAR = 2015
   OR SURVEY_YEAR = 2020
GROUP BY PF_CODE
)b
on a.PF_CODE = b.PF_CODE

WHERE b.Con2020 - b.Con2015 > 0
ORDER BY ROUND(((b.Con2020 - b.Con2015) * 100.0)/b.Con2015 ,1) desc
        ,a.PF_CODE