Select *,FORMAT((((52Hf / 51Hf)-1)*100),1) AS '% fark' from (
SELECT
....
FORMAT(SUM(IF(YEARWEEK(satis.IslemTarihi) = 201649, satis.SatisAdedi, 0)),1) AS 49Hf,
FORMAT(SUM(IF(YEARWEEK(satis.IslemTarihi) = 201650, satis.SatisAdedi, 0)),1) AS 50Hf,
FORMAT(SUM(IF(YEARWEEK(satis.IslemTarihi) = 201651, satis.SatisAdedi, 0)),1) AS 51Hf,
FORMAT(SUM(IF(YEARWEEK(satis.IslemTarihi) = 201652, satis.SatisAdedi, 0)),1) AS 52Hf
)
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