with
a(a1,a2,a3,a4)
as (
select
pr.pf_code,
pr.pf_name,
max(case po.survey_year when 2015 then po.total_amt else null end) ,
max(case po.survey_year when 2020 then po.total_amt else null end) 
from
POPU_TRANSITION po,
PREFECTURE pr
where
po.pf_code = pr.pf_code
and po.survey_year in ('2015','2020')
)
select 
a1 as '都道府県コード',
a2 as '都道府県名',
a3 as '総人口2015年',
a4 as '総人口2020年',
round(100*cast(cast(a4 as float)/cast(a3 as float) as float)) as '人口増加率'
from a
where a4 > a3
order by
'人口増加率' desc,1