WITH NEWDATA AS (
  SELECT
    MEMBER_CODE AS CODE,
    CHECKUP_DATE AS CK_DATE,
    WEIGHT,
    ROW_NUMBER() OVER (PARTITION BY MEMBER_CODE ORDER BY CHECKUP_DATE DESC) AS RN
  FROM
    HEALTH_CHECKUP
)
, WTS AS (
  SELECT
    MAX(CASE WHEN RN = 1 THEN CK_DATE END) AS CK_DATE,
    CODE,
    ROUND(MAX(CASE WHEN RN = 1 THEN WEIGHT END) * 10) - ROUND(MAX(CASE WHEN RN = 2 THEN WEIGHT END) * 10) AS CHG_WT
  FROM NEWDATA
  GROUP BY CODE
)
SELECT H.CK_DATE, H.CODE, (M.LAST_NAME || M.FIRST_NAME) AS NAME, ROUND(H.CHG_WT * 1.0 /10, 1) AS CHG_WT
  FROM WTS AS H
  INNER JOIN MEMBER_MST AS M
  ON H.CODE = M.MEMBER_CODE
  WHERE ABS(H.CHG_WT) >= 50
  ORDER BY H.CHG_WT DESC, H.CODE