Try this, sort of...

=A2-MIN(MAX(30-SUM(A$1:A1),0),A2)

here I assume there is not number in a1 and that the data starts in A2.
Fill down.

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If this helps, please click the Yes button.

Cheers,
Shane Devenshire


"ali" wrote:

hello

i have values

10
15
20
30
40

....from which i want to subtract 30, starting with the first number and
iterate through my list until i've completed the sum. so for example i would
eliminte the 10, 15 and part of of the 20 to be left with:

0
0
15
30
40

This is the first part of a bigger problem and ideally i'd like to attempt
it without any vba. is this even possible ??


thanks
ali