How to show the column that data first appear

[tuanvu]

Hi all

I have an Excel file as attached which show months in which we have order from customers.

Could you please help me the formula to show the month in which the customer first bought our product?

I have attached both the Excel file and an example picture.

Thank

File: https://files.fm/u/k4k9zk6t

 

[Fluff]

Hi & welcome to MrExcel.
How about

Excel 2013/2016
	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q	R	S	T	U
2	Customer ID	New customer in month	Jan-17	Feb-17	Mar-17	Apr-17	May-17	Jun-17	Jul-17	Aug-17	Sep-17	Oct-17	Nov-17	Dec-17	Jan-18	Feb-18	Mar-18	Apr-18	May-18	Jun-18
3	1	Nov-17											3	2	1		1	1	4	1
4	2	Jan-17	1	1		1	1	2	1			4	4	4	7	3	20	11	10	6
5	3	Mar-17			1		2			1	1		1	1	4		1		4	2
6	4	Apr-17				2							6				2	1	1	3
7	5	Aug-17								1				4			2			1
8	6	Mar-17			3			1	1		2	1	2	1	13	6	8	6	9	1
9	7	Jan-17	3	4	20	2	1	2	2	5	4		5	1	7	7	4	1	2
Sheet1

Cell Formulas
Range	Formula
C3	{=INDEX(D$2:U$2,,MATCH(TRUE,ISNUMBER(D3:U3),0))}
Press CTRL+SHIFT+ENTER to enter array formulas.

 

[Rick Rothstein]

[TABLE="width: 85%"]
<tbody>[TR]
[TD]Array Formulas[TABLE="width: 100%"]
<thead>[TR="bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=DAE7F5]#DAE7F5[/URL] "]
[TH="width: 10px"]Cell[/TH]
[TH="align: left"]Formula[/TH]
[/TR]
</thead><tbody>[TR]
[TH="width: 10px, bgcolor: [URL=https://www.mrexcel.com/forum/usertag.php?do=list&action=hash&hash=DAE7F5]#DAE7F5[/URL] "]C3[/TH]
[TD="align: left"]{=INDEX(D$2:U$2,,MATCH(TRUE,ISNUMBER(D3:U3),0))}[/TD]
[/TR]
</tbody>[/TABLE]
Entered with Ctrl+Shift+Enter. If entered correctly, Excel will surround with curly braces {}.
Note: Do not try and enter the {} manually yourself[/TD]
[/TR]
</tbody>[/TABLE]

Interestingly, your formula works even if you don't skip over the row argument...

=INDEX(D$2:U$2,MATCH(TRUE,ISNUMBER(D3:U3),0))

Here is an alternate (still array-entered**) formula that will also work...

=INDEX(D$2:U$2,MATCH(TRUE,D3:U3<>"",0))

**Commit this formula using CTRL+SHIFT+ENTER and not just Enter by itself

 

[Fluff]

Cross posted https://www.excelforum.com/excel-ge...olumn-that-data-first-appear.html#post5003994

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