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