WITH TMP_TABLE AS(
    SELECT
        TOTAL_VALUE,
        RANK() OVER(ORDER BY TOTAL_VALUE ASC) AS RNK_ASC,
        RANK() OVER(ORDER BY TOTAL_VALUE DESC) AS RNK_DESC
    FROM
        CONVENIENCE
    WHERE
        SURVEY_YEAR = 2019
        AND KIND_CODE = '100'
)
SELECT
    ROUND(AVG(TOTAL_VALUE), 0) AS SA_MEDIAN
FROM
    TMP_TABLE
WHERE
    ABS(RNK_ASC - RNK_DESC) <= 1