Find first row where values are not identical in all columns

[Pigankle]

[TABLE="width: 500"]
<tbody>[TR]
[TD][/TD]
[TD]A
[/TD]
[TD]B
[/TD]
[TD]C
[/TD]
[/TR]
[TR]
[TD]1
[/TD]
[TD]7/25
[/TD]
[TD]4.1
[/TD]
[TD]4.1
[/TD]
[/TR]
[TR]
[TD]2
[/TD]
[TD]7/26
[/TD]
[TD]5.09
[/TD]
[TD]5.09
[/TD]
[/TR]
[TR]
[TD]3
[/TD]
[TD]7/27
[/TD]
[TD]5.00
[/TD]
[TD]5.00
[/TD]
[/TR]
[TR]
[TD]4
[/TD]
[TD]7/28
[/TD]
[TD]4.88
[/TD]
[TD]4.88
[/TD]
[/TR]
[TR]
[TD]5
[/TD]
[TD]7/29
[/TD]
[TD]4.76
[/TD]
[TD]5.10
[/TD]
[/TR]
[TR]
[TD]6
[/TD]
[TD]7/30
[/TD]
[TD]4.79
[/TD]
[TD]5.02
[/TD]
[/TR]
</tbody>[/TABLE]

I have time series data that looks something like this. Values are identical across any row, up to some variable number of days in the future. After that, they are different in all columns. I would like a formula that will return the date corresponding to the first row in which not all cells are the same. For the sample data above, I would want the formula to return "7/29", since that is the value in column A for the first row in which columns B and C do not match.

I can kludge this by making another column that tests whether cells B# and C# match, then searching for the first "False.", but for a few reasons, that would not be an elegant solution. Can anyone help me out with a single-cell solution to this? It seems like there must be a way to do this with some crafty array formula and a couple of "match" arguments, but it is over my head.

 

[Marcelo Branco]

Maybe

=INDEX(A:A,MATCH(TRUE,INDEX($B$1:$B$100<>$C$1:$C$100,0),0))

M.

 

[Pigankle]

Holy cow, that was simple! Awesome and Muito Obrigado!

 

[Marcelo Branco]

Holy cow, that was simple! Awesome and Muito Obrigado!

Hey

You are welcome and thanks for the feedback.

De nada!

M.