SELECT ROUND(AVG(score)) AS SA_MEDIAN
FROM (
    SELECT *
        , TOTAL_VALUE AS score
        , ROW_NUMBER() OVER (ORDER BY TOTAL_VALUE) as row
        , COUNT(*) OVER () as total_rows
    FROM CONVENIENCE
    WHERE SURVEY_YEAR = 2019
      AND KIND_CODE   = '100'
  )
WHERE row in ((total_rows + 1) / 2, (total_rows + 2) / 2)
  AND SURVEY_YEAR = 2019
  AND KIND_CODE   = '100'