SELECT
  ROUND(AVG(x)) AS SA_MEDIAN
FROM (
    SELECT x
    FROM
        (
        SELECT
          TOTAL_VALUE AS x
        FROM
          CONVENIENCE
        WHERE
          SURVEY_YEAR = 2019
          AND KIND_CODE = 100
        )
    ORDER BY
      x
    LIMIT 2 - (SELECT COUNT(*) FROM (
         SELECT
          TOTAL_VALUE
        FROM
          CONVENIENCE
        WHERE
          SURVEY_YEAR = 2019
          AND KIND_CODE = 100)) % 2
    OFFSET (SELECT (COUNT(*)-1) / 2
            FROM (
                  SELECT
                    TOTAL_VALUE
                  FROM
                    CONVENIENCE
                  WHERE
                    SURVEY_YEAR = 2019
                    AND KIND_CODE = 100
            ))
)