WITH cte AS (
    SELECT LAT_N,
           ROW_NUMBER() OVER (ORDER BY LAT_N) AS ordena,
           COUNT(*) OVER () AS total_count
    FROM STATION
)

SELECT 
    ROUND(AVG(LAT_N), 4) AS median
FROM 
    cte
WHERE 
    ordena IN (FLOOR((total_count + 1) / 2), FLOOR((total_count + 2) / 2));