cumulative sum in aggregate query.

Hi there,

I have a query that gives me x/y data for a graph, and at the moment, 
the y data is relative.

EG:

x    |  y
1.2    | +1
1.9    | 0
3.4    | +4
5.2    | -2
6.7    | -1
9.3    | 0
11.3    | -1

Now, I want to convert this result into a result like this:
x    |  y
1.2    | 1
1.9    | 1
3.4    | 5
5.2    | 3
6.7    | 2
9.3    | 0
11.3    | 1

Does anyone have any suggestions as to how to do this?



--
Best Regards
David Stanaway
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Technology Manager  -  Australia's Premier Internet Broadcasters
david@NetVentures.com.au     Office +612 9357 1699
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