SELECT ROUND(AVG(t1_TOTAL_VALUE)) SA_MEDIAN
FROM (
  SELECT t1.TOTAL_VALUE as t1_TOTAL_VALUE
    FROM (SELECT TOTAL_VALUE
            FROM CONVENIENCE
           WHERE SURVEY_YEAR = 2019
             AND KIND_CODE = '100'
         ) t1
 CROSS JOIN (SELECT TOTAL_VALUE
               FROM CONVENIENCE
              WHERE SURVEY_YEAR = 2019
                AND KIND_CODE = '100'
             ) t2
GROUP BY t1.TOTAL_VALUE
HAVING SUM(CASE WHEN t1.TOTAL_VALUE >= t2.TOTAL_VALUE THEN 1 ELSE 0 END) >= COUNT(*)/2
AND SUM(CASE WHEN t1.TOTAL_VALUE <= t2.TOTAL_VALUE THEN 1 ELSE 0 END) >= COUNT(*)/2
)