SELECT ROUND(AVG(TOTAL_VALUE)) SA_MEDIAN FROM (
SELECT C1.TOTAL_VALUE
FROM
(
	SELECT TOTAL_VALUE
	FROM CONVENIENCE
	WHERE SURVEY_YEAR = '2019'
	AND KIND_CODE = '100'
) C1
 CROSS JOIN 
CONVENIENCE C2
GROUP BY C1.TOTAL_VALUE
HAVING SUM(case when C1.TOTAL_VALUE >= C2.TOTAL_VALUE then 1 else 0 end) >= count(*)/2
and SUM(case when C1.TOTAL_VALUE <= C2.TOTAL_VALUE then 1 else 0 end) >= count(*)/2
)