SELECT
ROUND(AVG(TOTAL_VALUE),0) AS SA_MEDIAN
FROM
(SELECT
*,
RANK()
OVER
(ORDER BY TOTAL_VALUE) AS RANK1,
RANK()
OVER
(ORDER BY TOTAL_VALUE DESC) AS RANK2

FROM CONVENIENCE
WHERE SURVEY_YEAR = 2019 AND KIND_CODE = 100)

WHERE ABS(RANK2 - RANK1) <= 1
;