[Tfug] oo.org spreadsheet formula question.

[Quag7]

Spreadsheets are things I need to use rarely but when I need them, I
*really* need them.

I have a spreadsheet tracking regular contributions to an investment.

I have a column (C) like this:

C
--
(Row 1) 100.00
(Row 2) 100.00
(Row 3) 100.00
(Row 4) 150.00
(Row 5) 100.00

I want column D to be a running total from the first value just up to
that specific row, so that  D2 would read $200, D3 would read $300, D4
would read $450.00 and so on.

I have been here 2 hours now trying to figure out how to do that without
having to enter specific cells in the =SUM() formula.  I'd hate to have
to use (for example) in row D2:

=SUM(C1:C2)

And then in D3

=SUM(C1:C3)

I'd like to have something like

=SUM(C1:C(thisrownumber))

I cannot figure out how to do this.  Does anyone have any experience
with this?

=CELL("ADDRESS") without any more arguments returns me something close
to what I am looking for but I have no idea how to incorporate this into
a =SUM() formula.

Any help would be appreciated.
 
  -C