select
PT1.PF_CODE as 都道府県コード 
,P.PF_NAME as 都道府県
,PT1.TOTAL_AMT as 総人口2015年
,PT2.TOTAL_AMT as 総人口2020年
, ROUND(
CAST(PT2.TOTAL_AMT as real)/
CAST(PT1.TOTAL_AMT as real)
 * 100
) as 人口増加率
from
POPU_TRANSITION as PT1
inner join PREFECTURE as P
on PT1.PF_CODE = P.PF_CODE
inner join POPU_TRANSITION as PT2
on PT1.PF_CODE = PT2.PF_CODE
and PT2.SURVEY_YEAR = 2020
where
PT1.SURVEY_YEAR = 2015
and PT2.TOTAL_AMT >= PT1.TOTAL_AMT
order by
人口増加率 desc
,都道府県コード asc;