SELECT ROUND(TOTAL_VALUE, 0) AS SA_MEDIAN
FROM (
    SELECT TOTAL_VALUE,
           ROW_NUMBER() OVER (ORDER BY TOTAL_VALUE) AS RN,
           COUNT(*) OVER () AS CNT
    FROM CONVENIENCE
    WHERE KIND_CODE = '100' AND SURVEY_YEAR = 2019
) t
WHERE RN IN ((CNT + 1) / 2, (CNT + 2) / 2);