with
	c as (
		select
			total_value
			,row_number() over(order by total_value) as row_num
			,count(pf_code) over() as num
		from
			convenience
		where
		    survey_year = 2019
		    and kind_code = '100'
	)
	
select
	round(avg(total_value), 0) as SA_MEDIAN
from
	c
where
	cast(num + 1 as real) / 2 - 0.5 <= row_num
	and row_num <= cast(num + 1 as real) / 2 + 0.5