select round(AVG(WORK.TOTAL_VALUE)) AS SA_MEDIAN

from(
    select *,
        row_number() OVER(
            order by CON.TOTAL_VALUE desc
        ) as ROWNUM,
        COUNT(1) OVER(PARTITION BY CON.KIND_CODE, CON.KIND_CODE) AS TOTAL_SUBJECT
    from CONVENIENCE as CON
    where CON.SURVEY_YEAR = '2019'
    and CON.KIND_CODE = '100'
    order by CON.TOTAL_VALUE desc
) as WORK
WHERE
    WORK.ROWNUM BETWEEN WORK.TOTAL_SUBJECT * 1.0 / 2
    AND WORK.TOTAL_SUBJECT * 1.0 / 2 + 1