WITH t1 AS (
SELECT TOTAL_VALUE
        , ROW_NUMBER() OVER (ORDER BY TOTAL_VALUE ASC) AS r_n
FROM CONVENIENCE
    WHERE
        SURVEY_YEAR = 2019
        AND KIND_CODE = '100'
)


SELECT ROUND(AVG(TOTAL_VALUE)) AS SA_MEDIAN
FROM (
    SELECT
        TOTAL_VALUE
        , r_n
        , MAX(r_n) OVER (PARTITION BY 1) AS m
    FROM t1
)
WHERE
    r_n BETWEEN m*1.0/2.0 AND m*1.0/2.0 + 1