essayez ceci
DECLARE @Table TABLE(
ID INT IDENTITY(1,1),
Descr VARCHAR(20),
Val FLOAT
)
INSERT INTO @Table (Descr,Val) SELECT 'X', 10
INSERT INTO @Table (Descr,Val) SELECT 'Y', 20
INSERT INTO @Table (Descr,Val) SELECT 'Z', 50
INSERT INTO @Table (Descr,Val) SELECT 'A', 75
INSERT INTO @Table (Descr,Val) SELECT 'B', 100
SELECT t1.Descr,
t1.Val,
SUM(ISNULL(t2.Val,0))
FROM @Table t1 LEFT JOIN
@Table t2 ON t1.ID >= t2.ID
GROUP BY t1.Descr,
t1.Val