SELECT
  ROUND(AVG(TAB.TOTAL))
  AS SA_MEDIAN
FROM
(
SELECT
  ROW_NUMBER() OVER(ORDER BY SUM(TOTAL_VALUE) DESC) AS RNUM
 ,SUM(TOTAL_VALUE) AS TOTAL
FROM CONVENIENCE
WHERE SURVEY_YEAR = '2019'
  AND KIND_CODE = '100'
GROUP BY PF_CODE
) TAB
WHERE
   RNUM = (SELECT ROUND(COUNT(*) / 2) AS MIN_ROW FROM CONVENIENCE WHERE SURVEY_YEAR = '2019' AND KIND_CODE = '100')
OR RNUM = (SELECT ROUND((SELECT ROUND(COUNT(*) / 2) AS MIN_ROW FROM CONVENIENCE WHERE SURVEY_YEAR = '2019' AND KIND_CODE = '100') + 1.0 / 2))