Your problem is that you're using single quotes, so "$row" doesn't get replaced with its value. 
# -1 per Mr. Muskrat
$worksheet->write($row-1, 6, "=SUM(C$row:E$row)"   );

[download]
I replaced "write_formula" with "write", since using that method results in formulas that work for me (although looking at the docs, that wasn't the problem. See Mr. Muskrat's excellent answer).

Oh, and if this doesn't work, you're in luck. The author of SS:WE hangs out here, so he'll probably know exactly what you need.
--
Mike

Edit: D'oh! Mr. Muskrat's right; the row is 0 based in the write_formula call, but 1-based in the formula.

In reply to Re: Couple of questions about Spreadsheet::WriteExcel by RMGir
in thread Couple of questions about Spreadsheet::WriteExcel by vxp

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