SELECT
AVG(WORK.TOTAL_VALUE) AS SA_MEDIAN
FROM
    (
        SELECT
            *,
            ROW_NUMBER() OVER (
                PARTITION BY TOTAL_VALUE
                ORDER BY
                    TOTAL_VALUE
            ) AS ROWNUM,
            COUNT(1) OVER(PARTITION BY TOTAL_VALUE) AS TOTAL_VALUE
        FROM
            CONVENIENCE
    ) WORK
WHERE
    WORK.ROWNUM BETWEEN WORK.TOTAL_VALUE * 1.0 / 2
    AND WORK.TOTAL_VALUE * 1.0 / 2 + 1
    AND SURVEY_YEAR = '2019'
GROUP BY
    WORK.TOTAL_VALUE;