SELECT ROUND(AVG(TOTAL_VALUE)) AS SA_MEDIAN
FROM (
    SELECT TOTAL_VALUE
    FROM CONVENIENCE
    WHERE SURVEY_YEAR = 2019 AND KIND_CODE = "100"
    ORDER BY TOTAL_VALUE
    LIMIT 2 - (SELECT COUNT(*) % 2 FROM CONVENIENCE)
    OFFSET (SELECT (COUNT(*) - 1) / 2 FROM CONVENIENCE)
);